Composition and Antiviral Activity of the Essential Oils of Eryngium alpinum and E. amethystinum

The chemical compositions of the essential oils obtained by hydrodistillation of the aerial parts of Croatian Eryngium alpinum L. and E. amethystinum L. were characterized by GC‐FID and GC/MS analyses. The main components identified were the sesquiterpene β‐caryophyllene (19.7%) in the oil of E. amethystinum and the oxygenated sesquiterpene caryophyllene oxide (21.6%) in the oil of E. alpinum. Overall, 32 and 35 constituents were detected in the essential oils of the aerial parts of E. alpinum and E. amethystinum, respectively, representing 92.4 and 93.1% of the total oil compositions. The essential oils of both Eryngium species were proved to reduce the number of lesions in the local host Chenopodium quinoa infected with cucumber mosaic virus and an associated satellite. This is the first investigation of antiphytoviral activity of essential oils of Eryngium species.     

Chemical Composition and Antimicrobial Activity of the Essential Oil from Aerial Parts and Roots of Eryngium barrelieri Boiss. and Eryngium glomeratum Lam. from Tunisia

The study of chemical composition and biological activity of unexplored essential oils may open new perspectives on their potential use in facing major health concerns such as drug‐resistant infections. The present study investigates the chemical composition and antimicrobial effects of previously unstudied essential oils obtained from genus Eryngium: Eryngium glomeratum Lam . and Eryngium barrelieri Boiss . The chemical compositions of the essential oils from aerial parts and roots of both species were studied using GC and GC/MS analytical technics. The analysis led to the identification of 102 compounds totalizing 85 – 94% of all detected compounds. Essential oils were characterized by the predominance of oxygenated sesquiterpenes. The oils obtained from aerial parts were tested against 36 microbial strains by agar dilution method and showed minimum inhibitory concentrations (MIC) in the range of 2 – 625 μg/ml. A strong antibacterial activity against multiresistant Pseudomonas aeruginosa was observed especially from E. glomeratum essential oil with MIC value up to 2 μg/ml. These findings give significant information about the pharmacological activity of these essential oils, which suggest their potential use to develop new remedies, or as sources of active compounds.     

Chemical Composition and Biological Investigations of Eryngium triquetrum Essential Oil from Algeria

The chemical composition, antibacterial and antioxidant activities of the essential oil obtained from Eryngium triquetrum from Algeria were studied. The chemical composition of sample oils from 25 locations was investigated using GC‐FID and GC/MS. Twenty‐four components representing always more than 87% were identified in essential oils from total aerial parts of plants, stems, flowers and roots. Falcarinol is highly dominant in the essential oil from the roots (95.5%). The relative abundance of falcarinol in the aerial parts correlates with the phenological stages of the plant. Aerial parts of E. triquetrum produce an essential oil dominated by falcarinol during the early flowering stage, and then there is a decrease in falcarinol and rebalancing of octanal during the flowering stage. To our knowledge, the present study is the first report of the chemical composition of E. triquetrum essential oil. Evaluation of the antibacterial activity by means of the paper disc diffusion method and minimum inhibitory concentration assays, showed a moderate efficiency of E. triquetrum essential oil. Using the DPPH method, the interesting antioxidant activity of E. triquetrum essential oil was established. These activities could be attributed to the dominance of falcarinol. The outcome of our literature search on the occurrence of falcarinol in essential oils suggests that E. triquetrum from Algeria could be considered as a possible source of natural falcarinol.     

Biological Activities of Phenolics from the Fruits of Phyllanthus emblica L. (Euphorbiaceae)

Seven phenolic compounds, 1 – 7 , including a new organic acid gallate, mucic acid 1‐ethyl 6‐methyl ester 2‐O‐gallate ( 7 ), were isolated from the MeOH extract of the fruits of Phyllanthus emblica L. (Euphorbiaceae). The structures were elucidated on the basis of extensive spectroscopic analysis and comparison with literature data. Upon evaluated for their antioxidant abilities by 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH), 2,2′‐azinobis(3‐ethylbenzthiazoline‐6‐sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays. The inhibitory activities against melanogenesis in B16 melanoma cells induced by α‐MSH, as well as cytotoxic activities against four human cancer cell lines were also evaluated. All phenolic compounds, 1 – 7 , exhibited potent antioxidant abilities (DPPH: IC₅₀ 5.6 – 12.9 μm ; ABTS: 0.87 – 8.43 μm Trolox/μm ; FRAP: 1.01 – 5.79 μm Fe²⁺/μm , respectively). Besides, 5 – 7 , also exhibited moderate inhibitory activities against melanogenesis (80.7 – 86.8% melanin content), even with no or low toxicity to the cells (93.5 – 101.6% cell viability) at a high concentration of 100 μm . Compounds 1 – 3 exhibited cytotoxic activity against one or more cell lines (IC₅₀ 13.9 – 68.4%), and compound 1 with high tumor selectivity for A549 (SI 3.2).     

Composition,Antioxidant, and Cytotoxic Activities of the Essential Oils from Fresh and Air‐Dried Aerial Parts of Pallenis spinosa

This study was performed to determine the chemical composition, antioxidant and cytotoxic effects of essential oils extracted from the aerial parts of fresh (F‐PSEO) and air‐dried (D‐PSEO) Pallenis spinosa. The composition of the oils was analyzed by gas chromatography (GC) and GC/mass spectrometry, the antioxidant activity by free radical scavenging and metal chelating assays, and their cytotoxicity by a flow cytometry analysis. The primary components in both oils were sesquiterpene hydrocarbons and oxygentated sesquiterpenes. F‐PSEO contained 36 different compounds; α‐cadinol (16.48%), germacra‐1(10),5‐diene‐3,4‐diol (14.45%), γ‐cadinene (12.03%), and α‐muurolol (9.89%) were the principal components. D‐PSEO contained 53 molecules; α‐cadinol (19.26%), δ‐cadinene (13.93%), α‐muurolol (12.88%), and germacra‐1(10),5‐diene‐3,4‐diol (8.41%) constituted the highest percentages. Although both oils exhibited a weak radical scavenging and chelating activity, compared to α‐tocopherol and ascorbic acid, D‐PSEO showed a 2‐fold greater antioxidant activity than F‐PSEO. Furthermore, low doses of F‐PSEO were able to inhibit the growth of leukemic (HL‐60, K562, and Jurkat) and solid tumor cells (MCF‐7, HepG2, HT‐1080, and Caco‐2) with an IC₅₀ range of 0.25 – 0.66 μg/ml and 0.50 – 2.35 μg/ml, respectively. F‐PSEO showed a ca. 2 – 3‐fold stronger cytotoxicity against the tested cells than D‐PSEO. The potent growth inhibitory effect of the plant essential oil encourages further studies to characterize the molecular mechanisms of its cytotoxicity.     

Chemical Composition Variability of Essential Oils of Daucus gracilis Steinh. from Algeria

The chemical compositions of 20 Algerian Daucus gracilis essential oils were investigated using GC‐FID, GC/MS, and NMR analyses. Altogether, 47 compounds were identified, accounting for 90 – 99% of the total oil compositions. The main components were linalool ( 18 ; 12.5 – 22.6%), 2‐methylbutyl 2‐methylbutyrate ( 20 ; 9.2 – 20.2%), 2‐methylbutyl isobutyrate ( 10 ; 4.2 – 12.2%), ammimajane ( 47 ; 2.6 – 37.1%), (E)‐β‐ocimene ( 15 ; 0.2 – 12.8%) and 3‐methylbutyl isovalerate ( 19 ; 3.3 – 9.6%). The chemical composition of the essential oils obtained from separate organs was also studied. GC and GC/MS analysis of D. gracilis leaves and flowers allowed identifying 47 compounds, amounting to 92.3% and 94.1% of total oil composition, respectively. GC and GC/MS analysis of D. gracilis leaf and flower oils allowed identifying linalool (22.7%), 2‐methylbutyl 2‐methylbutyrate (18.9%), 2‐methylbutyl isovalerate (13.6%), ammimajane (10.4%), 3‐methylbutyl isovalerate (10.3%), (E)‐β‐ocimene (8.4%) and isopentyl 2‐methylbutyrate (8.1%) as main components. The chemical variability of the Algerian oil samples was studied using statistical analysis, which allowed the discrimination of three main Groups. A direct correlation between the altitudes, nature of soils and the chemical compositions of the D. gracilis essential oils was evidenced.     

Chemical Composition and Antimicrobial Activity of Essential Oils from the Aerial Parts of Asteriscus graveolens (Forssk.) Less. and Pulicaria incisa (Lam.) DC.: Two Asteraceae Herbs Growing Wild in the Hoggar

In recent years, antimicrobial activities of essential oils have been intensively explored, mainly in researching and developing new antimicrobial agents to overcome microbial resistance. The present study investigates the chemical composition and antimicrobial activities of essential oils obtained from two Asteraceae: Asteriscus graveolens (Forssk .) Less . and Pulicaria incisa (Lam .) DC. Chemical analysis was performed using a combination of capillary GC‐FID and GC/MS analytical techniques. The major component of Asteriscus graveolens were cis‐chrysanthenyl acetate (31.1%), myrtenyl acetate (15.1%), and kessane (11.5%), while for Pulicaria incisa the main components were chrysanthenone (45.3%) and 2,6‐dimethylphenol (12.6%). The oils obtained from the aerial parts were tested against sixteen microbial strains by agar well diffusion technique and dilution methods and showed minimum inhibitory concentrations (MIC) in the range of 19 – 1250 μg/ml. A good antibacterial activity against a common nosocomial pathogen, Acinetobacter baumanniiATCC 19606 was observed, especially from Pulicaria incisa essential oil, with a MIC value up to 19 μg/ml. These results give significant information about the pharmacological activity of these essential oils, which suggest their benefits to human health, having the potential to be used for medical purposes.     

Composition and Biological Activity of Picea pungens and Picea orientalis Seed and Cone Essential Oils

The increasing consumption of natural products lead us to discover and study new plant materials, such as conifer seeds and cones, which could be easily available from the forest industry as a waste material, for their potential uses. The chemical composition of the essential oils of Picea pungens and Picea orientalis was fully characterized by GC and GC/MS methods. Seed and cone oils of both tree species were composed mainly of monoterpene hydrocarbons, among which limonene, α‐ and β‐pinene were the major, but in different proportions in the examined conifer essential oils. The levorotary form of chiral monoterpene molecules was predominant over the dextrorotary form. The composition of oils from P. pungens seeds and cones was similar, while the hydrodistilled oils of P. orientalis seeds and cones differed from each other, mainly by a higher amount of oxygenated derivatives of monoterpenes and by other higher molar mass terpenes in seed oil. The essential oils showed mild antimicrobial action, however P. orientalis cone oil exhibited stronger antimicrobial properties against tested bacterial species than those of P. pungens. Effects of the tested cone essential oils on human skin fibroblasts and microvascular endothelial cells (HMEC‐1) were similar: in a concentration of 0 – 0.075 μl/ml the oils were rather safe for human skin fibroblasts and 0 – 0.005 μl/ml for HMEC‐1 cells. IC₅₀ value of Picea pungens oils was 0.115 μl/ml, while that of Picea orientalis was 0.105 μl/ml. The value of IC₅₀ of both oils were 0.035 μl/ml for HMEC‐1 cells. The strongest effect on cell viability had the oil from Picea orientalis cones, while on DNA synthesis the oil from Picea pungens cones.     

Genetic and Chemical Diversity in Perovskia abrotanoides Kar. (Lamiaceae) Populations Based on ISSRs Markers and Essential Oils Profile

Genetic and the essential oil composition variability among twelve Perovskia abrotanoides populations (PAbPs) growing wild in Iran were assessed by ISSR markers, GC‐FID and GC/MS, respectively. Nine selected ISSR primers produced 119 discernible bands, of them 96 (80.7%) being polymorphic. Genetic similarity values among populations ranged between 0.07 and 0.79 which indicated a high level of genetic variation. Polymorphic information content, resolving power and marker index generated by ISSR primers were, 0.31, 6.14, and 3.32, respectively. UPGMA grouped PAbPs into four main clusters. Altogether, 38 chemical compounds were identified in the oils, and a relatively high variation in their contents was found. Camphor (11.9 – 27.5%), 1,8‐cineole (11.3 – 21.3%), α‐bisabolol (0.0 – 13.1%), α‐pinene (5.9 – 10.8%), and δ‐3‐carene (0.1 – 10.5%) were the major compounds. Oxygenated monoterpenes (32.1 – 35.8%) and monoterpene hydrocarbons (25.7 – 30.4%) were the main groups of compounds in the oils studied. Cluster analysis and principal‐component analysis were used to characterize the samples according to oil components. Four main chemotypes were found to be Chemotype I (camphor/1,8‐cineol), Chemotype II (1,8‐cineole/camphor), Chemotype III (camphor/1,8‐cineol/α‐bisabolol), and Chemotype IV (camphor/δ‐3‐carene/α‐bisabolol). The information, provided here on P. abrotanoides populations, will be useful to introduce this plant into agricultural systems.     

Influence of Morphological Variability and Habitat on the Chemical Composition of Essential Oils of an Algerian Endemic Origanum Species (Origanum floribundum Munby)

The genus Origanum L. (Lamiaceae) enjoys a socioeconomic interest and constitutes one of the most popular spices. In the literature, the study of this taxon is limited mainly to the chemical composition, antimicrobial, antifungal, and antioxidant activities of the essential oils. In Algeria, few works have been done in this area, including the endemic and rare species: Origanum floribundum Munby . In this study, our contribution highlights the influence of the ecological parameters and of the variation of morphological traits on the chemical composition and the antioxidant activity of the essential oils of six populations. The major oils constituents are carvacrol, γ‐terpinene, and p‐cymene with carvacrol predominance (31.8 – 60.8%) in over five populations (MS1 – MS4 and MS6). However, the population of Ain Terraeur (MS5) of which individuals present a foliar polymorphism, distinguishes itself by p‐cymene predominance (42.6%). This would denote a new chemotype and/or variety which seem well differentiated on the dendrogram of the Ascending Hierarchical Classification (A.H.C) and its foliar morphology. The antioxidant activity of the six samples evaluated by the scavenging activity of free radicals DPPH^? and ABTS^?+ showed a potent efficiency for the sample with foliar polymorphism population (IC₅₀ = 51.6 ± 0.31 and 12.71 ± 0.37 μg/ml, respectively).     

Variability of Pinus halepensis Mill. Essential Oils and Their Antioxidant Activities Depending on the Stage of Growth During Vegetative Cycle

The impact of growth stages during vegetative cycle (B₀ – B₅) on chemical composition and antioxidant activities of Pinus halepensis Mill . needles essential oils was investigated for the first time. GC and GC/MS analyses pointed to a quantitative variability of components; terpene hydrocarbons derivatives, represented by α‐pinene (8.5 – 12.9%), myrcene (17.5 – 21.6%), p‐cymene (7.9 – 11.9%) and (Z)‐β‐caryophyllene (17.3 – 21.2%) as major components, decreased from 88.9% at B₀ growth stage to 66.9% at B₅ growth stage, whereas oxygenated derivatives, represented by caryophyllene oxide (5.4 – 12.6%) and terpinen‐4‐ol (0.4 – 3.3%) as major components, increased from 7% at B₀ growth stage to 28.4% at B₅ growth stage. Furthermore, our findings showed that essential oil of P. halepensis needles collected at B₅ growth stage possess higher antioxidant activities by four different testing systems than those collected at B₀ – B₄ growth stages. This highlighted variability led to conclude that we should select essential oils to be investigated carefully depending on growth stage, in order to have the highest effectiveness of essential oil in terms of biological activities for human health purposes.     

Variation in Essential Oil and Bioactive Compounds of Curcuma kwangsiensis Collected from Natural Habitats

The chemical compositions of essential oils (EOs) extracted from Curcuma kwangsiensis rhizomes collected from six natural habitats in P. R. China were evaluated using gas chromatography/mass spectrometry (GC/MS). Fifty‐seven components were identified from the six EOs, and their main constituents were 8,9‐dehydro‐9‐formyl‐cycloisolongifolene (2.37 – 42.59%), germacrone (6.53 – 22.20%), and l ‐camphor (0.19 – 6.12%). The six EOs exhibited different DPPH radical‐scavenging activities (IC₅₀, 2.24 – 31.03 μg/ml), with the activity of most of EOs being much higher than that of Trolox C (IC₅₀, 10.49 μg/ml) and BHT (IC₅₀, 54.13 μg/ml). Most EOs had potent antimicrobial effects against the tested bacteria and fungus. They also exhibited cytotoxicity against B16 (IC₅₀, 4.44 – 147.4 μg/ml) and LNCaP cells (IC₅₀, 73.94 – 429.25 μg/ml). The EOs showed excellent anti‐inflammatory action by significantly downregulating expression of pro‐inflammatory cytokines, cyclooxygenase‐2, and tumor necrosis factor‐α. This study provides insight into the interrelation among growth location, phytoconstituents, and bioactivities, and the results indicate the potential of C. kwangsiensis as natural nutrients, medicines, and others additives.     

Chemical Composition,Antioxidant Properties, α‐Glucosidase Inhibitory,and Antimicrobial Activity of Essential Oils from Acacia mollissima and Acacia cyclops Cultivated in Tunisia

The genus Acacia is quite large and can be found in the warm subarid and arid parts, but little is known about its chemistry, especially the volatile parts. The volatile oils from fresh flowers of A. mollissima and A. cyclops (growing in Tunisia) obtained by hydrodistillation were analyzed by GC then GC/MS. Eighteen (94.7% of the total oil composition) and 23 (97.4%) compounds were identified in these oils, respectively. (E,E)‐α‐Farnesene (51.5%) and (E)‐cinnamyl alcohol (10.7%) constituted the major compounds of the flower oil of A. mollissima, while nonadecane (29.6%) and caryophyllene oxide (15.9%) were the main constituents of the essential oil of A. cyclops. Antioxidant activity of the isolated oils was studied by varied assays, i.e., 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and 2,2‐azinobis 3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS); the isolated oils showed lowest IC₅₀ (4 – 39 μg/ml) indicating their high antioxidant activity. The α‐glucosidase inhibitor activity was also evaluated and Acacia oils were found to be able to strongly inhibit this enzyme with IC₅₀ values (81 – 89 μg/ml) very close to that of acarbose which was used as positive control. Furthermore, they were tested against five Gram‐positive and Gram‐negative bacteria and one Candida species. Essential oil of A. mollissima was found to be more active than that of A. cyclops, especially against Pseudomonas aeruginosa (MIC = 0.31 mg/ml and MBC = 0.62 mg/ml).     

Chemical Composition,Antimicrobial and Cytotoxic Activity of Heracleum verticillatum Pančić and H. ternatum Velen. (Apiaceae) Essential Oils

In this work, the chemical composition, antimicrobial and cytotoxic activity of Heracleum verticillatum Pan?i? and H. ternatum Velen . root, leaf, and fruit essential oils were investigated. The composition was analyzed by GC and GC/MS. Heracleum verticillatum and H. ternatum root oils were dominated by monoterpenes, mostly β‐pinene (23.5% and 47.3%, respectively). Heracleum verticillatum leaf oil was characterized by monoterpenes, mainly limonene (20.3%), and sesquiterpenes, mostly (E)‐caryophyllene (19.1%), while H. ternatum leaf oil by the high percentage of phenylpropanoids, with (Z)‐isoelemicin (35.1%) being dominant constituent. Both fruit oils contained the majority of aliphatic esters, mostly octyl acetate (42.3% in H. verticillatum oil and 49.0% in H. ternatum oil). The antimicrobial activity of the oils was determined by microdilution method against eight bacterial and eight fungal strains. The strongest effect was exhibited by H. verticillatum root oil, particularly against Staphylococcus aureus, Salmonella typhimurium (MICs = 0.14 mg/ml, MBCs = 0.28 mg/ml), and Trichoderma viride (MIC = 0.05 mg/ml, MFC = 0.11 mg/ml). Cytotoxic effect was determined by MTT test against malignant HeLa, LS174, and A549 cells (IC₅₀ = 5.9 – 146.0 μg/ml), and against normal MRC‐5 cells (IC₅₀ > 120.1 μg/ml). The best effect was exhibited by H. verticillatum root oil on A549 cells (IC₅₀ = 5.9 μg/ml), and H. ternatum root oil against LS174 cells (IC₅₀ = 6.7 μg/ml).     

Analysis of Chemical Composition and Assessment of Antioxidant,Cytotoxic and Synergistic Antibacterial Activities of Essential Oils from Different Plant Parts of Piper boehmeriifolium

The essential oils (EOs) from leaves, stems, and whole plant of Piper boehmeriifolium were analyzed using GC/FID and GC/MS. The main constituents of P. boehmeriifolium EOs were β‐caryophyllene, caryophyllene oxide, β‐elemene, spathulenol, germacrene D, β‐selinene, and neointermedeol. The antioxidant potential of the EOs were determined using DPPH^?, ABTS^?+ and FRAP assays. In ABTS^?+ assay, the leaf oil exhibited a remarkable activity with an IC₅₀ value of 7.36 μg/mL almost similar to BHT (4.06 μg/mL). Furthermore, the antibacterial activity of the oils as well as their synergistic potential with conventional antibiotics were evaluated using microdilution and Checkerboard assays. The results revealed that the oils from different parts of P. boehmeriifolium inhibited the growth of all tested bacteria and the minimum inhibitory concentrations were determined to be 0.078 – 1.250 mg/mL. In combination with chloramphenicol or streptomycin, the oils showed significant synergistic antibacterial effects in most cases. Besides, the results of MTT assay indicated that the oil of the whole plant exhibited significant cytotoxic activities on human hepatocellular carcinoma cells (HepG2) and human breast cancer cells (MCF‐7). In summary, the P. boehmeriifolium oils could be regarded as a prospective source for pharmacologically active compounds.     

Variations in Essential Oil Composition and Antioxidant Activity in Perovskia abrotanoides Kar. Collected from Different Regions in Iran

Essential oil (EO) composition, phenolic content, and antioxidant activity were investigated in 17 P. abrotanoides populations collected from different geographical regions in Iran. The highest (3.61%) and lowest (1.25%) essential oil yields were measured in populations from Semnan Province (PSESM₂) and PISKS from Isfahan Province, respectively. GC/MS analysis identified camphor (4.05 – 35.94%), 1,8‐cineole (7.15 – 24.34%), borneol (0 – 21.75%), and α‐pinene (2.05 – 10.33%) as the main constituents of Perovskia essential oil. Cluster analysis classified the studied populations into four different groups: (I) high camphene, (II) high camphor/1,8‐cineole, (III) high borneol/δ‐3‐carene, and (IV) high α‐cadinol/trans‐caryophyllene. The highest flavonoid and phenolic contents were detected in PISAK from Isfahan Province (4.09 ± 0.05 mgQE/gDW, 58.51 ± 1.63 mgGAE/gDW) and PKRGS from Khorasan Province (3.80 ± 0.002 mgQE/gDW, 66.86 ± 0.002 mgGAE/gDW). DPPH and reducing power activity model systems identified PMASA and PKRKL as the populations with the highest antioxidant activity. Finally, the data obtained represented valuable information for introducing elite populations with EO components favorable to pharmaceutical and industrial applications.     

Chemical Composition and Antioxidant Activity of Essential Oils and Methanol Extracts of Different Parts from Juniperus rigida Siebold & Zucc.

The chemical composition and antioxidant activity of essential oils and MeOH extracts of stems, needles, and berries from Juniperus rigida were studied. The results indicated that the yield of essential oil from stems (2.5%) was higher than from needles (0.8%) and berries (1.0%). The gas chromatography/mass spectrometer (GC/MS) analysis indicated that 21, 17, and 14 compounds were identified from stems, needles, and berries essential oils, respectively. Caryophyllene, α‐caryophyllene, and caryophyllene oxide were primary compounds in both stems and needles essential oils. However, α‐pinene and β‐myrcene mainly existed in berries essential oils and α‐ionone only in needles essential oils. The high‐performance liquid chromatography (HPLC) analysis indicated that the phenolic profiles of three parts exhibited significant differences. Needles extracts had the highest content of chlorogenic acid, catechin, podophyllotoxin, and amentoflavone, and for berries extracts, the content of those compounds was the lowest. Meanwhile, three in vitro methods (DPPH, ABTS, and FRAP) were used to evaluate antioxidant activity. Stems essential oil and needles extracts exhibited the powerful antioxidant activity than other parts. This is the first comprehensive study on the different parts of J. rigida. The results suggested that stems and needles of J. rigida are useful supplements for healthy products as new resources.     

Essential Oil Variability in Natural Populations of Artemisia campestris (L.) and Artemisia herba‐alba (Asso) and Incidence on Antiacetylcholinesterase and Antioxidant Activities

The intraspecific variability of Artemisia herba‐alba and A. campestris essential oils and the evaluation of their antioxidant and antiacetylcholinesterase activities were determined. Artemisia herba‐alba essential oil was found rich in camphor (19.61%), α‐thujone (19.40%), β‐thujone (9.44%), chrysanthenone (9.26%), and trans‐sabinyl acetate (8.43%). The major compounds of A. campestris essential oil were germacrene D (16.38%), β‐pinene (16.33%), and limonene (9.17%). Significant variation in the essential oil composition was observed among populations of each species. The divergence between populations was attributed to the variation of some climatic factors such as altitude, annual rainfall, winter cold stress, summer precipitation, summer drought stress, evapotranspiration, and humidity. Artemisia herba‐alba and A. campestris essential oils exhibited promising antioxidant and antiacetylcholinesterase activities. The level of activity varied significantly according to the species and the essential oil. The highest scavenging activity (IC₅₀ = 0.14 mg/ml) and the uppermost capacity to prevent β‐carotene bleaching (IC₅₀ = 0.10 mg/ml) characterized A. campestris from population 6. A. campestris population 3 possessed the uppermost ability to reduce ferric ions (450.7 μmol Fe²⁺/g EO). The population 2 of A. campestris showed the strongest antiacetylcholinesterase activity (IC₅₀ = 0.02 mg/ml). The variation of these activities between the essential oils was explained by their composition differences.     

Diterpenoids from Wedelia prostrata and Their Derivatives and Cytotoxic Activities

One new ent‐kaurane diterpenoid, 11β,16α‐dihydroxy‐ent‐kauran‐19‐oic acid ( 1 ), together with eight known analogues 2 – 9 were isolated from the aerial parts of Wedelia prostrata. One of the acidic diterpenoids, kaurenoic acid ( 3 ), was converted to seven derivatives, 10 – 16 . All compounds were evaluated for their cytotoxic activity in vitro against human leukemia (K562), liver (HepG‐2), and stomach (SGC‐7901) cancer cell lines. Only four kaurenoic acid derivatives, 13 – 16 , with 15‐keto and substitutions at C(19) position, exhibited notable cytotoxic activities on these tumor cell lines with IC₅₀ value ranging from 0.05 to 3.71 μm . Compounds 10 – 12 , with oxime on C(15) showed moderate inhibitory effects and compounds 1 – 9 showed no cytotoxicities on them. Structure–activity relationships were also discussed based on the experimental data obtained. The known derivative, 15‐oxokaurenoic acid 4‐piperdin‐1‐ylbutyl ester ( 17 ), induced typical apoptotic cell death in colon SW480 cells upon evaluation of the apoptosis‐inducing activity by flow‐cytometric analysis.     

Bioactive Constituents of Juniperus turbinata Guss. from La Maddalena Archipelago

A comprehensive phytochemical study of Juniperus turbinata (Cupressaceae) collected from La Maddalena Archipelago (Sardinia, Italy) is reported. Both the essential oil and the ethanolic extract obtained from the aerial parts were analyzed. The essential oil appears to belong to a new chemotype compared to other Mediterranean juniper accessions, as it was favored by geographic isolation of the isles. It showed a low content of monoterpene hydrocarbons and α‐terpineol, ent‐manoyl oxide, 1,10‐di‐epi‐cubenol as the major constituents. The ethanolic fraction contained mainly diterpenoids. Among these, 15‐formyloxyimbricatolic acid ( 7 ) is a new natural product since it has hitherto been obtained only by synthetic route. The phenolic fraction contained biflavonoids: cupressuflavone ( 9 ), followed by minor amounts of amentoflavone ( 10 ) and hinokiflavone ( 11 ). The essential oil and six purified compounds ( 1 – 4 , 8 and 9 ) were assessed for biological activities, namely antioxidant (assessed by DPPH^·, ABTS^·+ and FRAP methods) and cytotoxic effects towards selected human tumor cell lines (MDA‐MB 231, A375 and HCT116 cells). Compound 3 exhibited higher radical scavenging activity against ABTS^·+ radical than the reference Trolox. Noteworthy, compound 8 showed powerful effects towards tumor cell lines, with IC₅₀ values in the range of 0.060 – 0.201 μm , which make it a promising anticancer drug candidate.