Monoterpene content in Origanum syriacum as affected by environmental conditions and flowering

A high content of essential oil in the foliage of two chemotypes of field-grown Origanum syriacum L. was found between August and October. The content of phenolic monoterpenes in the essential oil was low from November to January, while the content of p -cymene was high. The effect of environmental conditions and flowering on the two chemotypes was similar. Controlled experiments revealed that under long photoperiods the content of essential oils in the foliage and of phenolic monoterpenes in the oil increased, while that of p -cymene decreased. A similar effect was observed when an 8 h natural light day was extended by 8 h low-intensity incandescent light. When the 16 h day was composed of 12 h natural light, the effect on oil content and composition was intensified. Under short-day photoperiods, increasing temperature or light intensity enhanced the relative content of p -cymene, while that of phenolic monoterpenes and the γ-terpinene generally decreased. Flowering decreased the essential oil content in the leaves and the relative content of the phenolic monoterpenes in the essential oil. Since environmental conditions influence flowering, they had both direct and indirect effects on the essential oil content and composition.     

Monoterpene and pregnane glucosides from Solenostemma argel

From the aerial parts of Solenostemma argel, two monoterpene glucosides have been isolated and identified as 6,7-dihydroxy-dihydrolinalool 3-O-beta-glucopyranoside and 6,7-dihydroxy-dihydrolinalool 7-O-beta-glucopyranoside. A pregnane glucoside was also isolated and assigned as pregn-5-ene-3,14-beta-dihydroxy-7,20-dione 3-O-beta-glucopyranoside together with the known compounds benzyl alcohol O-beta-apiofuranosyl-(1-->6)-beta-glucopyranoside, 2-phenylethyl O-alpha-arabinopyranosyl-(1-->6)-beta-glucopyranoside, astragalin and kaempferol-3-O-alpha-rhamnopyranosyl-(1-->2)-beta-glucopyranoside.     

In vitro amoebicidal activity of Origanum syriacum and Origanum laevigatum on Acanthamoeba castellanii cysts and trophozoites

In some patients, complete treatment of amoebic keratitis is difficult because of the resistance of cysts to therapeutic agents. The aim of this study was to evaluate the in vitro amoebicidal activity of methanolic extracts of Origanum syriacum and Origanum laevigatum. In the presence of methanolic extracts (ranging from 1.0 to 32.0mg/ml), numbers of the viable Acanthamoeba castellanii trophozoites and cysts were decreased. Both extracts showed a time and dose dependent amoebicidal action on the trophozoites and cysts. Of the extracts tested, O. syriacum showed the stronger amoebicidal effect on the trophozoites and cysts. In the presence of 32 mg/ml extract, no viable trophozoites were observed within third hour. The extract was also found effective against the cysts within 24th hour. In the case of O. laevigatum, no viable trophozoites were observed within 72nd hour at the concentrations of 16 and 32 mg/ml. As expected, cysts were found more resistant to the extracts than the trophozoites.     

Chemical Composition and Antimicrobial Activity of Origanum libanoticum,Origanum ehrenbergii,and Origanum syriacum Growing Wild in Lebanon

The essential oils (EOs) of the aerial parts of Origanum libanoticum and Origanum ehrenbergii, endemic to Lebanon, and Origanum syriacum, endemic to the Levantine, were obtained by distillation with a Clevenger apparatus. GC and GC/MS allowed identification of 96.4%, 93.5%, and 95.2% of their constituents, respectively. Carvacrol was the major component of both O. syriacum EO (79%) and O. ehrenbergii EO (60.8%). This compound was absent in O. libanoticum EO and the major compounds were β‐caryophyllene (26.8%), caryophyllene oxide (22.6%), and germacrene D (17.2%). The assessment of their antimicrobial activity against Candida albicans and six pathogenic bacteria revealed that O. libanoticum EO was inactive, while O. syriacum and O. ehrenbergii showed moderate antimicrobial activity with minimal inhibitory concentrations varying from 400 to 1200 μg/ml. These results support the traditional use of these last two species in traditional herbal preparations in Lebanon.     

Chemometric Tools to Highlight the Variability of the Chemical Composition and Yield of Lebanese Origanum syriacum L. Essential Oil

This study deals with the variation in the yield and composition of Lebanese Origanum syriacum L. essential oil (EO) according to harvesting time, drying methods used, and geographical location. Plant material was harvested twice a month all over 2013 and 2014 from Qartaba and Achkout located at high altitude and from Byblos at low altitude. EOs of the aerial parts were obtained by hydrodistillation. The highest yields were obtained at full flowering stage and slightly reduced after flowering. The GC/MS analysis revealed the presence of 50 components representing 90.49 – 99.82%, 88.79 – 100%, and 95.28 – 100% of the total oil extracted from plants harvested from Qartaba, Achkout, and Byblos, respectively. The major components in the oils were: carvacrol (2.1 – 79.8%), thymol (0.3 – 83.7%), p‐cymene (2.8 – 43.8%), thymoquinone (0.4 – 27.7%), γ‐terpinene (0.4 – 10.0%), octan‐3‐ol (0.3 – 4.9%), caryophyllene oxide (0.2 – 4.7%), oct‐1‐en‐3‐ol (0.3 – 3.7%), β‐caryophyllene (0.7 – 3.2%), cis‐sabinene hydrate (0.1 – 2.8%), terpinen‐4‐ol (0.1 – 2.8%), and α‐terpinene (0.2 – 2.2%). Independent components analysis (ICA) revealed that two groups were discriminated, reflecting compositional differences in the EOs profiles of the Lebanese oregano samples: O. syriacum grown in Qartaba and Achkout belongs to carvacrol chemotype, while O. syriacum grown in Byblos belongs to thymol chemotype. The flowering phase was the most productive period in terms of yield, bringing marked changes in the EO composition by increasing the amounts of carvacrol or thymol, and decreasing those of thymoquinone and p‐cymene.     

Monoterpene coumarins from Ferula ferulago.

Two monoterpene coumarins, designated ferulagol A and B, as well as three known monoterpene coumarins and three sesquiterpene lactones were isolated from the chloroform extract of the roots of Ferula ferulago. The structures of ferulagol A and B were determined to be 7-[(E)-3'-hydroxy-3',7'-dimethyl-4',6'-octadienyloxy]coumarin and 7-[(3'Z,5'E)-7'-hydroxy-3',7'-dimethyl-3',5'-octadienyloxy]coumarin, respectively.     

Monoterpene glycosides from Paeonia hybrida

Monoterpene glycosides (1–5, and 7), together with 14 known compounds, were isolated from the methanol extract of the roots of Paeonia hybrida. These compounds included a paeoniflorin-related glycoside with a hybrid structure of paeoniflorin and paeonovicinoside (1), a monoterpene glucoside biogenetically related to lactiflorin (2), a paeoniflorin-related monoterpene (3), arbiflorin-related monoterpenes (4 and 5), and a tymol-related monoterpene glycoside (7). Their structures were elucidated by extensive spectroscopic examinations.     

Generation of primary amide glucosides from cyanogenic glucosides

The cyanogenic glucoside-related compound prunasinamide, (2R)-β-d-glucopyranosyloxyacetamide, has been detected in dried, but not in fresh leaves of the prunasin-containing species Olinia ventosa, Prunus laurocerasus, Pteridium aquilinium and Holocalyx balansae. Experiments with leaves of O. ventosa indicated a connection between amide generation and an excessive production of reactive oxygen species. In vitro, the Radziszewski reaction with H₂O₂ has been performed to yield high amounts of prunasinamide from prunasin. This reaction is suggested to produce primary amides from cyanogenic glycosides in drying and decaying leaves. Two different benzoic acid esters which may be connected to prunasin metabolism were isolated and identified as the main constituents of chlorotic leaves from O. ventosa and P. laurocerasus.     

Iridoid glucosides from Veronica pectinata var. glandulosa

A new highly oxygenated iridoid glucoside, urphoside B (1) was isolated from the Veronica pectinata var. glandulosa together with seven known iridoid glucosides, aucubin, catalpol, veronicoside, catalposide, verproside, amphicoside and 6-O-veratroyl catalpol. The planar as well as the stereo structures of the isolated compounds were determined by means of extensive 1D- and 2D-NMR spectroscopy and confirmed by HR-Mass.     

羽叶鬼灯檠中的单萜二糖苷

从羽叶鬼灯檠 (RodgersiapinnataFranch .)的根茎中分离得到 6个单萜二糖苷 ,它们的结构通过波谱方法分别鉴定为 :(E ) 3,7 dimethyl 1 O [α L rhamnopyranosyl (1→ 6 ) β D glu copyranosyl] oct 2 en 7 ol (1) ,(E ) 3,7 dimethyl 1 O [α L arabinofuranosyl (1→ 6 ) β D glucopy ranosyl] oct 2 en 7 ol (2 ) ,geranyl 1 O α L arabinofuranosyl (1→ 6 ) β D glucopyranoside (3) ,gera nyl 1 O α L rhamnopyranosyl (1→ 6 ) β D glucopyranoside (4 ) ,geranyl 1 O β D xylopyranosyl (1→6 ) β D glucopyranoside (5 ) ,geranyl 1 O α L arabinopyranosyl (1→ 6 ) β D glucopyranoside (6 )。其中化合物 1为新化合物 ,单萜二糖苷类化合物系首次在该属中发现。     

Iridoid glucosides from Melampyrum

Melampyrum arvense and M. cristatum contain, besides aucubin, 8-epiloganin and melampyroside, a new natural iridoid glucoside: gardoside methyl ester. In addition, M. arvense contains mussaenoside and M. cristatum mussaenosidic acid, another novel iridoid glucoside.     

Monoterpene glycosides isolated from Fadogia agrestis

Six monoterpene glycosides were isolated from Fadogia agrestis. Their structures were elucidated using a combination of mass spectroscopy, 1D- and 2D-homo- and hetero-NMR spectroscopy and chemical analysis, and established as being derivatives of 2,6-dimethyl-2(E),6(Z)-octadiene-1,8-diol containing from two to four units of rhamnopyranose and, three of them, one or two additional units of glucopyranose. In three of the compounds an acyl group of 8-hydroxy-2,6-dimethyl-2(E),6(Z)-octadienoyl was found esterifying the O-2 position of one of the units of rhamnopyranose.     

Iridoid glucosides from Kickxia abhaica D.A. Sutton from Scrophulariaceae

Two iridoid glucosides namely; 6-acetylantirrinoside (1), 6'-O-p-hydroxybenzoylantirrinoside (2) were isolated from the aerial parts of Kickxia abhaica. Beside that, three known iridoid glucosides, antirrinoside (3), antirride (4) and mussaenosidic acid (5), one flavone glycoside (6) and a hexitol, d-mannitol (7) were isolated. The structures of the iridoid glucosides 1-2 were established by 1D and 2D NMR spectral data, including COSY, HMQC and HMBC experiments, as well as HRMS.     

Flavonoid glucosides from licorice

Two new flavanone glycosides, liquiritigenin 4′-apiosyl(1 → 2)-glucoside and liquiritigenin 7,4′-diglucoside together with a known flavone, apigenin 6,8-di-C-glucoside, have been isolated from licorice.     

Three dihydroisocoumarin glucosides from Hydrangea macrophylla subsp. serrata

Three new dihydroisocoumarin glucosides, macrophyllosides A, B and C were obtained from dry leaves of Hydrangea macrophylla subsp. serrata, together with the previously known hydrangenol 8-β-glucoside. Using NMR and CD techniques and some chemical transformation, the structures were elucidated as (3S)-3′,4′,5′-trimethoxyphenyl-8-β-D-glucopyranosyl dihydroisocoumarin, (3R and (3S)-3′,5′-dimethoxy-4′-hydroxyphenyl-8-β-D-glucopyranosyl dihydroisocoumarins. CD experiments indicated that hydrangenol 8-β-glucoside was the mixture of 3S- and 3R- stereoisomers.     

鞭打绣球中的一个新单萜苷

从鞭打绣球(Hemiphragma　heterophyllum　Wall.)全草中分离到1个新单萜苷和7个已知化合物。通过波谱数据分析,新单萜苷的结构鉴定为(4S)-α-萜烯醇-8-O-β-D-吡喃木糖-(1→6)-β-D-吡喃葡萄糖苷,已知化合物分别鉴定为globularin　(2)、(2S,　3S,　4R,　9E)-1,　3,　4-trihydroxy-2-[(2'R)-hydroxy-tetracosanoylamino]-9-octadecene　(3)、　β-香树素(4)、齐墩果酸　(5)、肉桂酸　(6)、β-谷甾醇　(7)和胡萝卜甙　(8)。除化合物2外,其余化合物均为首次从鞭打绣球中分离得到。     

鞭打绣球中的一个新单萜苷

从鞭打绣球(Hemiphragma heterophyllum Wall.)全草中分离到1个新单萜苷和7个已知化合物.通过波谱数据分析,新单萜苷的结构鉴定为(4S)-α-萜烯醇-8-O-β-D-比喃木糖-(1→6)-β-D-比喃葡萄糖苷,已知化合物分别鉴定为globularin(2)、(2S 3S,4R,9E)-1,3,4-trihydroxy-2-[(2'R)-hydroxy-tetracosanoylamino]-9-octadecene(3)、β-香树素(4)、齐墩果酸(5)、肉桂酸(6)、β-谷甾醇(7)和胡萝卜甙(8).除化合物2外,其余化合物均为首次从鞭打绣球中分离得到.     

Regeneration of plants from callus cultures of Origanum vulgare L.

Investigations were undertaken to achieve rapid multiplication and improvement of Origanum vulgare (a herbaceous, ornamental plant well known for its aromatic and medicinal value) through plant regeneration from callus. The explants (cotyledons, hypocotyl and root segments) excised from 15 d old aseptic seedlings were cultured on Gamborg's B₅ medium supplemented with 2,4-D, NAA and BAP individually and in various combinations (at concentrations of 0,10^–7,10^–6 and 10^–5 M). Best callus induction was noted on medium with 10^–7 M 2,4-D alone. The cotyledonary expiants proved to be the best source for compact and nodulated callus. The subcultured cotyledonary calli showed shoot induction when transferred onto media supplemented with BAP alone orin combination with 10^–7M or 10^–6MNAA. However, 10^–5M NAA completely suppressed the shoot inducing ability of BAP. In general, NAA promoted root induction from all explants used including cotyledonary callus. Best shoot induction was obtained on medium supplemented with 10^–6M BAP+10^–6MNAA. Both IBA and NAA at 10^–6 M proved to be equally effective in induction of roots from the cut ends of 15–20 mm long shoots (excised from callus) in half-strength B₅ liquid medium. Rooted shoots were successfully re-established in soil under controlled conditions.Abbreviations 2,4-D 2,4 dichlorophenoxyacetic acid - IBA indole-3-butyric acid - NAA -naphthaleneacetic acid - BAP 6-benzylaminopurine