Composition and Chemical Variability of Ivoirian Polyalthia oliveri Leaf Oil

The chemical composition of 45 essential oil samples isolated from the leaves of Polyalthia oliveri harvested in three Ivoirian forests was investigated by GC‐FID (retention indices measured on two columns of different polarities), and by ¹³C‐NMR, following a method developed in our laboratory. In total, 41 components were identified. The content of the main components varied drastically from sample to sample: (E)‐β‐caryophyllene (1.2 – 50.8%), α‐humulene (0.6 – 47.7%), isoguaiene (0 – 27.9%), alloaromadendrene (0 – 24.7%), germacrene B (0 – 18.3%), δ‐cadinene (0.4 – 19.3%), and β‐selinene (0.2 – 18.5%). The analysis of six oil samples selected in function of their chromatographic profiles is reported in detail. The 45 oil compositions were submitted to hierarchical cluster and principal components analysis, which allowed the distinction of three groups within the oil samples. The compositions of the oils from group I (15 samples) and II (12 samples) were dominated by (E)‐β‐caryophyllene and α‐humulene, respectively. Oil samples of group III (18 samples) needed to be partitioned into four subgroups III.1–III.4 whose compositions were dominated by alloaromadenrene, isoguaiene, germacrene B, and δ‐cadinene, respectively.     

Variation of Chemical Composition in Flowers and Leaves Essential Oils Among Natural Population of Tunisian Glebionis coronaria (L.) Tzvelev (Asteraceae)

The aim of this study was to assess the percentage and constituents variations in flowers and leaves essential oil of three Glebionis coronaria (L.) Tzvelev population, growing wildly in three different ecotypes (Utique, M'saken, and Sahara Lektar) in Tunisia. The chemical compositions of these essential oils were analyzed by the GC and GC/MS systems. Qualitative and quantitative differences were recorded between essential oils extracted from plants collected from the three geographical provinces and between organs of the same plant (leaves and flowers). In fact, 161 components representing 87.2 – 96.5% of the whole oils were identified. Myrcene (3.2 – 35.7%), (Z)‐β‐ocimene (0.6 – 23.0%), camphor (0.6 – 17.2%), cis‐chrysanthenol (0 – 6.9%), cis‐chrysanthenyl acetate (1.1 – 17.9%), isobornyl acetate (1.6 – 3.5%), (E)‐β‐farnesene (0 – 6.0%), germacrene D (0 – 8.7%), and (E,E)‐α‐farnesene (0.7 – 12.4%) were the predominant components in the oils. These major constituents occur in different amounts depending on the organs (leaves or flowers) and the geographical origin of the plant. The chemotaxonomic usefulness of these data was discussed according to results of principal component analysis (PCA). The scores, together with the loadings, revealed a different chemical pattern for each population.     

Chemical Composition and Allelopathic,Antibacterial, Antifungal,and Antiacetylcholinesterase Activity of Fish‐mint (Houttuynia cordataThunb.) from India

Fish‐mint (Houttuynia cordataThunb .), belonging to family Saururaceae, has long been used as food and traditional herbal medicine. The present study was framed to assess the changes occurring in the essential‐oil composition of H. cordata during annual growth and to evaluate allelopathic, antibacterial, antifungal, and antiacetylcholinesterase activities. The essential‐oil content ranged from 0.06 – 0.14% and 0.08 – 0.16% in aerial parts and underground stem, respectively. The essential oils were analysed by GC‐FID, GC/MS, and NMR (¹H and ¹³C). Major constituents of aerial‐parts oil was 2‐undecanone (19.4 – 56.3%), myrcene (2.6 – 44.3%), ethyl decanoate (0.0 – 10.6%), ethyl dodecanoate (1.1 – 8.6%), 2‐tridecanone (0.5 – 8.3%), and decanal (1.1 – 6.9%). However, major constituents of underground‐stem oil were 2‐undecanone (29.5 – 42.3%), myrcene (14.4 – 20.8%), sabinene (6.0 – 11.1%), 2‐tridecanone (1.8 – 10.5%), β‐pinene (5.3 – 10.0%), and ethyl dodecanoate (0.8 – 7.3%). Cluster analysis revealed that essential‐oil composition varied substantially due to the plant parts and season of collection. The oils exhibited significant allelopathic (inhibition: 77.8 – 88.8%; LD₅₀: 2.45 – 3.05 μl/plate), antibacterial (MIC: 0.52 – 2.08 μl/ml; MBC: bacteriostatic) and antifungal (MIC: 2.08 – 33.33 μl/ml; MFC: 4.16 – 33.33 μl/ml) activities. The results indicate that the essential oil from H. cordata has a significant potential to allow future exploration and exploitation as a natural antimicrobial and allelopathic agent.     

Biological Activities of Triterpenoids and Phenolic Compounds from Myrica cerifera Bark

Seven triterpenoids, 1  –  7 , two diarylheptanoids, 8 and 9 , four phenolic compounds, 10  –  13 , and three other compounds, 14  –  16 , were isolated from the hexane and MeOH extracts of the bark of Myrica cerifera L. (Myricaceae). Among these compounds, betulin ( 1 ), ursolic acid ( 3 ), and myricanol ( 8 ) exhibited cytotoxic activities against HL60 (leukemia), A549 (lung), and SK‐BR‐3 (breast) human cancer cell lines (IC₅₀ 3.1 – 24.2 μm ). Compound 8 induced apoptotic cell death in HL60 cells (IC₅₀ 5.3 μm ) upon evaluation of the apoptosis‐inducing activity by flow cytometric analysis and by Hoechst 33342 staining method. Western blot analysis on HL60 cells revealed that 8 activated caspases‐3, ‐8, and ‐9 suggesting that 8 induced apoptosis via both mitochondrial and death receptor pathways in HL60. Upon evaluation of the melanogenesis‐inhibitory activity in B16 melanoma cells induced with α‐melanocyte‐stimulating hormone (α‐MSH), erythrodiol ( 7 ), 4‐hydroxy‐2‐methoxyphenyl β‐d ‐glucopyranoside ( 13 ), and butyl quinate ( 15 ) exhibited inhibitory effects (65.4 – 86.0% melanin content) with no, or almost no, toxicity to the cells (85.9 – 107.4% cell viability) at 100 μm concentration. In addition, 8 , myricanone ( 9 ), myricitrin ( 10 ), protocatechuic acid ( 11 ), and gallic acid ( 12 ) revealed potent DPPH radical‐scavenging activities (IC₅₀ 6.9 – 20.5 μm ).     

Melanogenesis‐Inhibitory and Cytotoxic Activities of Limonoids,Alkaloids, and Phenolic Compounds from Phellodendron amurense Bark

Four limonoids, 1  –  4 , five alkaloids, 5  –  9 , and four phenolic compounds, 10  –  13 , were isolated from a MeOH extract of the bark of Phellodendron amurense (Rutaceae). Among these, compound 13 was new, and its structure was established as rel‐(1R,2R,3R)‐5‐hydroxy‐3‐(4‐hydroxy‐3‐methoxyphenyl)‐6‐methoxy‐1‐(methoxycarbonylmethyl)indane‐2‐carboxylic acid methyl ester (γ‐di(methyl ferulate)) based on the spectrometric analysis. Upon evaluation of compounds 1  –  13 against the melanogenesis in the B16 melanoma cells induced with α‐melanocyte‐stimulating hormone (α‐MSH), four compounds, limonin ( 1 ), noroxyhydrastinine ( 6 ), haplopine ( 7 ), and 4‐methoxy‐1‐methylquinolin‐2(1H)‐one ( 8 ), exhibited potent melanogenesis‐inhibitory activities with almost no toxicity to the cells. Western blot analysis revealed that compound 6 inhibited melanogenesis, at least in part, by inhibiting the expression of protein levels of tyrosinase, TRP‐1, and TRP‐2 in α‐MSH‐stimulated B16 melanoma cells. In addition, when compounds 1  –  13 were evaluated for their cytotoxic activities against leukemia (HL60), lung (A549), duodenum (AZ521), and breast (SK‐BR‐3) cancer cell lines, five compounds, berberine ( 5 ), 8 , canthin‐6‐one ( 9 ), α‐di‐(methyl ferulate) ( 12 ), and 13 , exhibited cytotoxicities against one or more cancer cell lines with IC₅₀ values in the range of 2.6 – 90.0 μm . In particular, compound 5 exhibited strong cytotoxicity against AZ521 (IC₅₀ 2.6 μm ) which was superior to that of the reference cisplatin (IC₅₀ 9.5 μm ).     

Chemical Variability of Ivoirian Xylopia rubescens Leaf Oil

Forty‐two essential oil samples were isolated from leaves of Xylopia rubescens harvested in three forests of Southern Ivory Coast. All the samples have been submitted to GC‐FID and the retention indices (RIs) of individual components have been measured on two capillary columns of different polarity. In addition, 20 oil samples, selected on the basis of their chromatographic profile, were also analyzed by ¹³C‐NMR and 24 components (78.0 – 92.4% of the whole compositions) have been identified. The content of the main components varied drastically from sample to sample: furanoguaia‐1,4‐diene (5.7 – 54.1%), furanoguaia‐1,3‐diene (1.1 – 10.5%), (8Z,11Z,14Z)‐heptadeca‐8,11,14‐trien‐2‐one (4.3 – 16.0%), and (E)‐β‐caryophyllene (1.7 – 17.3%). Hierarchical cluster and principal components analysis of the 42 oil compositions allowed the distinction of two well‐differentiated groups of unequal importance within the oil samples. Oil samples of the main group (Group II) contained mainly furanoguaia‐1,4‐diene (mean [M] = 43.1%; standard deviation [SD] = 3.2%) while furanoguaia‐1,3‐diene (M = 8.4%; SD = 0.9%) and (8Z,11Z,14Z)‐heptadeca‐8,11,14‐trien‐2‐one (M = 7.1%; SD = 1.5%) were present at appreciable contents. The composition of Group I was dominated by furanoguaia‐1,4‐diene (M = 17.0%; SD = 8.5%), (8Z,11Z,14Z)‐heptadeca‐8,11,14‐trien‐2‐one (M = 10.2%; SD = 2.4%) and (E)‐β‐caryophyllene (M = 9.5%; SD = 5.3%).     

Chemical Variability,Antioxidant and Antifungal Activities of Essential Oils and Hydrosol Extract of Calendula arvensis L. from Western Algeria

The chemical composition of the essential oils and hydrosol extract from aerial parts of Calendula arvensis L. was investigated using GC‐FID and GC/MS. Intra‐species variations of the chemical compositions of essential oils from 18 Algerian sample locations were investigated using statistical analysis. Chemical analysis allowed the identification of 53 compounds amounting to 92.3 – 98.5% with yields varied of 0.09 – 0.36% and the main compounds were zingiberenol 1 (8.7 – 29.8%), eremoligenol (4.2 – 12.5%), β‐curcumene (2.1 – 12.5%), zingiberenol 2 (4.6 – 19.8%) and (E,Z)‐farnesol (3.5 – 23.4%). The study of the chemical variability of essential oils allowed the discrimination of two main clusters confirming that there is a relation between the essential oil compositions and the harvest locations. Different concentrations of essential oil and hydrosol extract were prepared and their antioxidant activity were assessed using three methods (2,2‐diphenyl‐1‐picrylhydrazyl, Ferric‐Reducing Antioxidant Power Assay and β‐carotene). The results showed that hydrosol extract presented an interesting antioxidant activity. The in vitro antifungal activity of hydrosol extract produced the best antifungal inhibition against Penicillium expansum and Aspergillus niger, while, essential oil was inhibitory at relatively higher concentrations. Results showed that the treatments of pear fruits with essential oil and hydrosol extract presented a very interesting protective activity on disease severity of pears caused by P. expansum.     

Four New Tirucallane Triterpenoids from the Fruits of Melia azedarach and Their Cytotoxic Activities

Four new tirucallane triterpenoids, (21S,23R,24R)‐21,23‐epoxy‐21,24‐dihydroxy‐25‐methoxytirucall‐7‐en‐3‐one ( 2 ), (3S,21S,23R,24S)‐21,23‐epoxy‐21,25‐dimethoxytirucall‐7‐ene‐3,24‐diol ( 8 ), (21S,23R,24R)‐21,23‐epoxy‐24‐hydroxy‐21‐methoxytirucalla‐7,25‐dien‐3‐one ( 11 ), and (21S,23R,24R)‐21,23‐epoxy‐21,24‐dihydroxytirucalla‐7,25‐dien‐3‐one ( 12 ), along with 16 known analogues, 1 , 3  –  7 , 9  –  10 , and 13  –  20 , were isolated from the fruits of Melia azedarach. Their structures were elucidated by spectroscopic methods including 1D‐ and 2D‐NMR techniques and mass spectrometry. These compounds were evaluated for their cytotoxicities against HepG2 (liver), SGC7901 (stomach), K562 (leukemia), and HL60 (leukemia) cancer cell lines. Compound 20 exhibited potent cytotoxicity against HepG2 and SGC7901 cancer cells with the IC₅₀ values of 6.9 and 6.9 μm , respectively.     

Chemical Compositions,Antioxidant and Antimicrobial Activities of Essential Oils of Psidium guajava L. Leaves from Different Geographic Regions in China

Hydrodistilled essential oils (EO) of Psidium guajava L. leaves from different regions in China were analyzed by GC and GC/MS. The samples from Guangdong Province displayed high EO yields (0.61 – 0.75%, v/w). A total of 50 components, representing over 98.00% of the EOs, were identified and semi‐quantitatived. The major constituents of EOs included β‐caryophyllene (17.17 – 31.38%), γ‐gurjunene (9.17 – 15.22%), τ‐cadinol (1.35 – 10.02%) and calamenene (2.13 – 7.80%). The terpenoids in all sample oils were dominated by sesquiterpenes hydrocarbons (70.18 – 84.35%), followed by oxygenated sesquiterpenes (9.89 – 22.19%). The similarities and differences among EOs from different samples were evaluated by hierarchical cluster analysis and principal component analysis methods. The IC₅₀ values of EOs from different regions were between 18.52 – 33.72 mg/ml (DPPH) and 13.12 – 25.15 mg/ml (ABTS⁺). The FRAP value of EO from Guangdong Province was 7.34 – 9.13 mmol Vc/g DM, while the FRAP value of EO from Taiwan Province was 2.29 – 2.36 mmol Vc/g DM. The antimicrobial tests revealed that EO had a higher antimicrobial activity against all Gram‐positive bacteria and two fungi. Moreover, EO from P. guajava leaves of Guangdong Province showed the highest antimicrobial activity. These properties can be considered in the design of industrial products and for further application in the food, pharmaceutical and cosmetic industries.     

Variation in Essential Oil Yield and Composition of Dorema aucheri Boiss., an Endemic Medicinal Plant Collected from Wild Populations in Natural Habitats

In the present research, variability in essential oil (EO) composition of five Dorema aucheri populations collected from natural habitats in different regions of Iran, were investigated. The EO content of populations varied from 0.28 to 0.68%. According to gas chromatography/mass spectrometry analysis, β‐caryophyllene (7.17 – 35.73%), thymol (23.45 – 29.64%), β‐gurjunene (2.58 – 5.89%), carvacrol (1.32 – 2.67%) and cuparene (1.97 – 2.98%) were the major components. Hierarchical cluster, principal component and canonical correspondence analyses classified the studied populations into three groups based on major EO components. The environmental parameters of the collected sites were also evaluated. According to the results, it might be suggested that sandy soils with high mean annual precipitation were major environmental factors influencing the amount of β‐caryophyllene, while thymol, cuparene and caryophyllen oxide increased in silty and clay soils. Finally, the population collected in high altitudes and clay soils had higher amount of β‐gurjunene.     

Fatty Acid Patterns of Seeds of Some Salvia Species from Iran – A Chemotaxonomic Approach

In this study, the seed oil content and fatty acid (FA) profile of 21 populations from 16 wild Salvia species of Iran were analyzed by GC. Patterns of chemical variations of the oils among species were identified via numerical analyses and also the taxonomic status of the infrageneric grouping was outlined in the genus. Salvia species were scored based on the contents of main FAs using principal coordinate analysis (PCO). The results showed that the total oil content in the seeds varied significantly, and ranged from 6.68 to 38.53% dry weight. α‐Linolenic (18:3ω3, 1.69 – 53.56%), linoleic (18:2ω6, 13.04 – 60.64%), oleic (18:1ω9, 6.15 – 27.06%), palmitic (16:0, 3.77 – 9.27%), and stearic (18:0, 1.78 – 3.05%) acid were identified as five major FAs in the oils. The amount of ω‐3 and ω‐6 FAs ranged between 1.90 – 53.80% and 13.46 – 60.83% of total FAs in the seed oils, respectively. The results confirmed that FA profiles were distinctive among the species and that they can be used as chemotaxonomic markers. The discrimination of Salvia species according to their botanical classification at intersectional level was supported. In general, seed oils of Salvia species were rich sources of polyunsaturated FAs, except in linoleic and α‐linolenic acid, and may be valuable for food and pharmaceutical industries.     

Superbanone,A New 2‐Aryl‐3‐benzofuranone and Other Bioactive Constituents from the Tube Roots of Butea superba

Phytochemical investigation from the tube roots of Butea superba, led to the isolation and identification of a new 2‐aryl‐3‐benzofuranone named superbanone ( 1 ), one benzoin, 2‐hydroxy‐1‐(2‐hydroxy‐4‐methoxyphenyl)‐2‐(4‐methoxyphenyl)ethanone ( 2 ), eight pterocarpans ( 3  –  10 ), and eleven isoflavonoids ( 11  –  21 ). Compound 2 was identified for the first time as a natural product. The structure of the isolated compounds was elucidated using spectroscopic methods, mainly 1D‐ and 2D‐NMR. The isolated compounds and their derivatives were evaluated for α‐glucosidase inhibitory and antimalarial activities. Compounds 3 , 7 , 8 , and 11 showed promising α‐glucosidase inhibitory activity (IC₅₀ = 13.71 ± 0.54, 23.54 ± 0.75, 28.83 ± 1.02, and 12.35 ± 0.36 μm , respectively). Compounds 3 and 11 were twofold less active than the standard drug acarbose (IC₅₀ = 6.54 ± 0.04 μm ). None of the tested compounds was found to be active against Plasmodium falciparum strain 94. On the basis of biological activity results, structure–activity relationships are discussed.     

Chemical Polymorphism of Origanum compactum Grown in All Natural Habitats in Morocco

Origanum compactum L. (Lamiaceae) is one of the most important medicinal species in term of ethnobotany in Morocco. It is considered as a very threatened species as it is heavily exploited. Its domestication remains the most efficient way to safeguard it for future generations. For this purpose, wide evaluation of the existing variability in all over the Moroccan territory is required. The essential oils of 527 individual plants belonging to 88 populations collected from the whole distribution area of the species in Morocco were analyzed by GC/MS. The dominant constituents were carvacrol (0 – 96.3%), thymol (0 – 80.7%), p‐cymene (0.2 – 58.6%), γ‐terpinene (0 – 35.2%), carvacryl methyl ether (0 – 36.2%), and α‐terpineol (0 – 25.8%). While in the Middle Atlas region and the Central Morocco mainly carvacrol type samples were found, much higher chemotypic diversity was encountered within samples from the north part of Morocco (occidental and central Rif regions). The high chemical polymorphism of plants offers a wide range for selection of valuable chemotypes, as a part of breeding and domestication programs of this threatened species.     

Constituents from the Roots of Actinidia chinensis and Their Cytochrome P450 Enzyme Inhibitory Activities

A newly discovered triterpenoid, (2α,3β)‐2,3,23‐trihydroxyurs‐13(18)‐en‐28‐oic acid ( 1 ), along with twelve known compounds ( 2  –  13 ), were isolated from the roots of Actinidia chinensis Planch (Actinidiaceae). Their chemical structures were determined by 1D‐ and 2D‐NMR spectra and mass spectrometry (MS). The crude extracts and six main constituents ( 8  –  13 ) were tested for cytochrome P450 (CYPs) enzyme inhibitory activity. The results showed that, except for compound 8 , compounds 9  –  13 had different inhibitory effects on the cytochrome P450 (CYPs) enzyme, and compound 9 significantly inhibited the catalytic activities of CYP3A4 to < 10% of its control activities.     

13,14‐seco‐Withanolides from Physalis minima with Potential Anti‐inflammatory Activity

Four new 13,14‐seco‐withanolides, minisecolides A – D ( 1  –  4 ), together with three known analogues 5  –  7 , were isolated from the whole plants of Physalis minima. The structures of new compounds were determined on the basis of spectroscopic analysis, including ¹H‐, ¹³C‐NMR, 2D‐NMR (HMBC, HSQC, ROESY), and HR‐ESI‐MS. Evaluation of all isolates for their inhibitory effects on nitric oxide (NO) production was conducted on lipopolysaccaride‐activated RAW264.7 macrophages. Compounds 2 , 3 , 5 , and 6 showed inhibitory activities, especially for compound 5 with IC₅₀ value of 3.87 μm .     

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.     

Four New Kaurane Diterpenoids from the Chinese Liverwort Jungermannia comata Nees

In our continuing program to find new bioactive compounds from the Chinese liverworts, four new kaurane‐type diterpenoids, (6β)‐kaur‐16‐ene‐6,9‐diol ( 1 ), (6β,12β)‐kaur‐16‐ene‐6,9,12‐triol ( 2 ), (6β)‐kaur‐16‐ene‐5,6,9‐triol ( 3 ), and kaur‐16‐ene‐9,19‐diol ( 4 ), have been isolated from the Chinese liverwort Jungermannia comata Nees . Five known kaurane‐type diterpenoids ( 5  –  9 ) and four known trachylobane‐type diterpenoids ( 10  –  13 ) were also obtained. The structures of the new compounds were established unequivocally on the basis of spectroscopic data. The absolute configuration of compound 1 was established by comparing experimental and calculated electronic circular dichroism spectra.     

Variation in Chemical Composition and Antibacterial Activity of the Essential Oil of Wild Populations of Phlomis olivieri

Various species of the genus Phlomis have been reported to produce metabolites demonstrating significant pharmacological efficiency. In this study, the essential oils from twelve populations of Phlomis olivieri collected from natural habitats were investigated for their chemical components. The hydrodistillated essential oil analyzed by GC‐FID and GC/MS. Analyses revealed 27 compounds, constituting 90.52 – 98.51% of the essential oils. Results indicated that the major components of the essential oils from various populations of P. olivieri were germacrene D (26.54 – 56.41%), bicyclogermacrene (6.38 – 30.55%), β‐caryophyllene (5.32 – 24.52%) and α‐pinene (1.29 – 15.53%). Principal component analyses (PCA) was used to identify any geographical variations in essential oil composition. Notably, three groups of Iranian P. olivieri populations were determined according to the major compounds. Results of the in vitro antibacterial activity indicated that P. olivieri essential oils showed good inhibitory activities against bacteria, especially Bacillus subtilis. The results of this study gave new insights for cultivation and industrial uses of P. olivieri in Iran.     

Six New Polyhydroxysteroidal Glycosides,Anthenosides S1 – S6, from the Starfish Anthenea sibogae

Six new polyhydroxysteroidal glycosides, anthenosides S1  –  S6 ( 1  –  6 ), along with a mixture of two previously known related glycosides, 7 and 8 , were isolated from the methanolic extract of the starfish Anthenea sibogae. The structures of 1  –  6 were established by NMR and HR‐ESI‐MS techniques as well as by chemical transformations. All new compounds have a 5α‐cholest‐8(14)‐ene‐3α,6β,7β,16α‐tetrahydroxysteroidal nucleus and differ from majority of starfish glycosides in positions of carbohydrate moieties at C(7) and C(16) ( 1  –  4 , 6 ) or only at C(16) ( 5 ). The 4‐O‐methyl‐β‐d ‐glucopyranose residue ( 2 ) and Δ²⁴‐cholestane side chain ( 3 ) have not been found earlier in the starfish steroidal glycosides. The mixture of 7 and 8 slightly inhibited the proliferation of human breast cancer T‐47D cells and decreased the colony size in the colony formation assay.     

Variations in Essential Oil Compositions of Lavandula pubescens (Lamiaceae) Aerial Parts Growing Wild in Yemen

Lavandula pubescens Decne . is one of five Lavandula species growing wild in Yemen. The plant is used in Yemeni traditional medicine, and the essential oil tends to be rich in carvacrol. In this work, L. pubescens was collected from eight different locations in Yemen, the essential oils obtained by hydrodistillation, and the oils analyzed by gas chromatography/mass spectrometry (GC/MS). Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to differentiate between the L. pubescens samples. The essential oils were rich in carvacrol (60.9 – 77.5%), with lesser concentrations of carvacrol methyl ether (4.0 – 11.4%), caryophyllene oxide (2.1 – 6.9%), and terpinolene (0.6 – 9.2%). The essential oil compositions in this study showed very high similarity, but it was possible to discern two separate groups based on minor components, in particular the concentrations of terpinolene, carvacrol methyl ether, m‐cymen‐8‐ol, and caryophyllene oxide.