Composition and antimicrobial activity of the essential oil of Ballota pseudodictamnus L. Bentham.

The chemical composition of the essential oil of Ballota pseudodictamnus obtained from the aerial parts was analysed by GC/MS. From the 52 identified constituents of the oil, caryophyllene oxide, phytol and gamma-muurolene were the major components. Furthermore, the essential oil was investigated for its antimicrobial activity.

Essential oils and hexane extracts from leaves and fruits of Cistus monspeliensis. Cytotoxic activity of ent-13-epi-manoyl oxide and its isomers.

Essential oils and hexane extracts from Cistus monspeliensis L. leaves and fruits were analysed by GC-MS. Manoyl oxide and its isomers, 3 beta-hydroxy-manoyl oxide, 3 beta-hydroxy-13-epi-manoyl oxide, as well as 3 beta-acetoxy-13-epi-manoyl oxide were detected for the first time in C. monspeliensis L. Ent-13-epimanoyl oxide was isolated from the hexane extract of leaves and its structure was determined using spectroscopic methods. In vitro cytotoxic activity of ent-13-epi-manoyl oxide and mixtures of manoyl oxide isomers at 10(-4) M concentrations ranged from 11.1 to 32.2% of the activity for a vinblastine control evaluated against nine leukemic cell lines. The results showed that the manoyl oxide isomer mixtures as well as ent-13-epi-manoyl oxide exhibited a slight growth inhibiting activity.

Composition and antibacterial activity of the essential oils of Stachys candida and S. chrysantha from southern Greece.

The chemical composition of the essential oils obtained from the aerial parts of Stachys candida and S. chrysantha were analysed with GC and GC/MS. Forty-two constituents were identified from the two oils and alpha-cadinol, manoyl oxide, caryophyllene oxide, epi-alpha-muurolol and (E)-caryophyllene were found to be the major components. Furthermore, the oils were tested against six Gram (+/-) bacteria and it was found that one of them exhibited significant antibacterial activity.

Analysis of labdane-type diterpenes from Cistus creticus (subsp. creticus and subsp. eriocephalus), by GC and GC-MS.

The qualitative and quantitative analysis of labdane-type diterpenes of the hexane extracts and of the essential oils of the leaves, fruits and resin "Ladano", of Cistus creticus subsp. creticus and Cistus creticus subsp. eriocephalus, have been carried out by GC and GC-MS analysis using two capillary chromatographic columns, i.e., HP-5MS and CP-Wax. The methanolic extract of the fruits of C. creticus subsp. creticus was examined and seven labdane diterpenes were isolated and identified by spectroscopic methods. Data on the investigation of labdane diterpenes by GC and GC-MS is limited and most of them have never been analysed by this method. The results obtained by this analysis could be useful for identifying them in crude plant extracts. Manoyl oxides were studied further for the percentage content of their isomers. The hexane extracts of the two subspecies as well as the manoyl oxide isomers isolated from the methanolic extract of the fruits of C. creticus subsp. creticus, were tested for their antimicrobial activity against Gram-positive and Gram-negative bacteria. Global numerical differences of these C. creticus subspecies, based on labdane diterpenes content in the hexane extracts as well as in the essential oils, were established by statistical methods. Phenotypic differences are discussed.

Volatile constituents of bracts and leaves of wild and cultivated Origanum dictamnus.

The chemical composition of the volatile constituents from bracts and leaves of wild and hydroponically cultivated ORIGANUM DICTOMNUS were analysed by GC and GC-MS. Three different levels of nitrogen (100,150, 200 mg/l), were used in the nutrient solution for the cultivation, using the Nutrient Film Technique (N.F.T). Carvacrol was the predominant compound in all cases. The essential oils were investigated for their antimicrobial activity against STAPHYLOCOCCUS AUREUS, STAPHYLOCOCCUS EPIDERMIDIS, STAPHYLOCOCCUS HOMINIS, ESCHEIRICHIA COLI, and PSEUDOMONOS AERUGINOSA.

Cytotoxic coumarins from the aerial parts of Tordylium apulum and their effects on a non-small-cell bronchial carcinoma line.

Seven coumarins were isolated from the aerial parts of Tordylium apulum; their structures were established by spectroscopic means. All compounds were tested in vitro for their cytotoxicity against two cell line systems. The antiproliferative effects for three of them were studied at the level of the cell cycle in asynchronous cells of the NSCLC-N6 line with a flow cytometry apparatus.

Cytotoxic coumarins from the aerial parts of Tordylium apulum and their effects on a non-small-cell bronchial carcinoma cell line.

Seven coumarins were isolated from the aerial parts of Tordylium apulum; their structures were established by spectroscopic means. All compounds were tested in vitro for their cytotoxicity against two cell line systems. The antiproliferative effects for three of them were studied at the level of the cell cycle in asynchronous cells of the NSCLC-N6 line with a flow cytometry apparatus.

Composition and antimicrobial activity of the essential oil of Cistus creticus subsp. eriocephalus.

The chemical composition of the essential oil of the leaves of Cistus creticus subsp. eriocephalus (Viv.) Greuter & Burdet, (Cistaceae), was investigated by GC/MS. Thirty-nine components were identified, representing 73.9% (based on % total peak area by GC) of the oil composition. The main components of the oil were alpha-cadinene (6.5%), delta-cadinene (5.6%), viridiflorol (5.4%), bulnesol (6.3%), ledol (3.8%), alpha-copaene (3.8%), beta-selinene (3.4%), cubenene (3.3%), manoyl oxide (9.9%) and 13-epi-manoyl oxide (3.4%). Antibacterial studies were carried out in vitro against Gram-positive and Gram-negative organisms.

Chemical and antibacterial studies of two Helichrysum species of Greek origin.

The chemical composition of the essential oils obtained from the aerial parts of Helichrysum stoechas ssp. barrelieri and H. taenari was analysed by GC and GC/MS. From the thirty-nine identified constituents representing the 73.87% and 87.41% of the two oils, respectively, beta-elemene, beta-caryophyllene, geraniol, and camphene were the major components. Furthermore, it was found that the oils exhibited significant antibacterial activity against six Gram (+/-) bacteria.

Chemical and biological studies on two Helichrysum species of Greek origin.

The chemical composition of the essential oils obtained from the aerial parts of Helichrysum amorginum and H.italicum were analysed with GC and GC/MS. From the twenty-five identified constituents representing the 89.98% and 82.06% of the two oils respectively, geraniol, geranyl acetate, neryl acetate, and nerolidol were the major components. Furthermore, it was found that the oils exhibited definite antibacterial activity against the six tested Gram (+/-) bacteria.