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Conium divaricatum, even though exhibiting morphological differences in comparison to its congener of European origin Conium maculatum, is still considered a disputed taxon often referred to as a synonym of the latter. Herein, essential oils of various plant tissues from several populations of both taxa were comparatively investigated, showing distinct chemical profiles. In the case of C. divaricatum, the essential oils were dominated by hydrocarbon esters, among which the main constituents 4'-oxodecyl hexanoate, 4'-oxododecyl hexanoate and 4'-oxooctyl hexanoate were isolated and identified as undescribed natural products. In contrast, the essential oils of C. maculatum were dominated by hydrocarbon alkanes, alkenes and ketones, as well as the polyacetylene (Z)-falcarinol. Even though determination of the total alkaloids content and toxicity assessment against the crustacean Artemia salina did not reveal significant differences, the distinct chemical profiles and the morphological differences observed for both taxa, strongly support their distinction as separate species.

Dinoflagellates contain large amounts of omega-3 fatty acids, including the nutritionally important docosahexaenoic acid (DHA). However, their cultivation in suspensions is characterized by low growth rates. Twin-layer porous substrate photobioreactors (TL-PSBRs) have been shown to support growth of different microalgal species, including the robust dinoflagellate Symbiodinium voratum. In the present study, the potential of cultivating marine autotrophic dinoflagellate species in a TL-PSBR for DHA production was explored. Based on initial screening experiments, two Symbiodinium species with high biomass and DHA productivities were selected: the symbiotic Symbiodinium microadriaticum CCAC 2475 B and the free-living Symbiodinium voratum CCAC 3869 B. The effects of three different temperatures (17, 22 and 27 °C) and nitrogen regimes (nitrate, ammonium and nitrogen-free) on biomass growth, total lipid accumulation and fatty acid methyl esters (FAMEs) content, with emphasis on DHA, were evaluated. The two lower temperatures (17 and 22 °C) enhanced growth and total lipid accumulation of S. microadriaticum CCAC 2475 B and S. voratum CCAC 3869 B. Cultivation at 22 °C and nitrogen limitation led to a significant positive effect on DHA productivity. Symbiodinium. microadriaticum CCAC 2475 B reached a DHA productivity of 145.4 mg m−2 day−1 and DHA content in the dry biomass of 2% (w/w) after 4 days of nitrogen depletion. The results of the present study demonstrated that autotrophic dinoflagellates, when cultivated on a TL-PSBR, produce comparable amounts of lipids and fatty acids to other commercially used microalgal species including the valuable DHA.

Within the framework of finding new fumigants, less toxic and environmentally friendly, in comparison with conventional fumigants, natural products and essential oils are considered to be alternative sources of potentially active compounds. In this context, the aim of the present study was the chemical analysis and the evaluation of fumigant toxicity against the adults of rice weevil Sitophylus oryzae of sixteen essential oils obtained from fourteen plant species. The essential oils of the species Apium nodiflorum, Bupleurum fruticosum, Crithmum maritimum, Liquidambar orientalis and Laurus azorica consisted mainly of monoterpene hydrocarbons. Oxygenated monoterpenes were the prevailing group of compounds in the essential oils of Laurus nobilis, Myrtus communis, Salvia fruticosa S. pomifera subsp. calycina, S. officinalis and Thymbra capitata. The essential oils of Cotinus coggygria, S. microphylla and Teucrium capitatum were rich in sesquiterpenes. The most active essential oils were those of T. capitata (LC50 = 3.4 μL/L air) and S. pomifera subsp. calycina (LC50 = 4.4 μL/L air) against S. oryzae adults. The essential oils of S. fruticosa, L. nobilis and S. officinalis were also found to be highly toxic (LC50 = 7.4–15.5 μL/L air). Most of the other essential oils tested exhibited moderate to low toxicities (LC50 = 17.7–37.9 μL/L air), while those of C. coggygria and S. microphylla did not exhibit any noticeable activity. Our results indicate that some essential oils, and in particular those of T. capitata and S. pomifera subsp. calycina might be promising fumigants for the control of important pests of stored grain such as the rice weevil S. oryzae.

Dried leaves of commercially available Salvia officinalis, Salvia fruticosa, and Melissa officinalis were divided into two parts; the first part was subjected to hydrodistillation and the second part was used for the preparation of the infusions. The essential oil and the infusion of each sample were subjected to analysis by means of GC-FID and GC-MS. The oxygenated monoterpenes 1,8-cineole (27.5%) and camphor (11.5%) appeared as the most important metabolites in Salvia officinalis, α- and β-thujone (16.5%, 16.4%), followed by 1,8-cineole (8.8%) were characterizing the essential oil of Salvia fruticosa, whereas in the oil of Melissa officinalis the sesquiterpene caryophyllene oxide (14.9%) was the most abundant constituent, followed by geranial (12.2%), neral (11.2%) and citronellal (6.7%). The infusions were characterized by the higher levels of the most important compounds found in the essential oil of the respective sample, as in the case of S. officinalis (1,8-cineol 53.6%, camphor 25.8%) and S. fruticosa (α- thujone 61.2%, β-thujone 24.3%, 1,8-cineole 14.5%), while the infusion of M. officinalis was dominated by palmitic and stearic acid (25.5%, 19.5%).

Thuwalallenes A&ndash, E (1&ndash, 3, 5 and 8) and thuwalenynes A&ndash, C (4, 6, 7), new C15 acetogenins featuring uncommon ring systems, along with cis-maneonene D (9), thyrsiferol (10) and 23-acetyl-thyrsiferol (11) were isolated from the organic extract of a population of the red alga Laurencia sp., collected at Rose Reef off the village of Thuwal in the Red Sea waters of the Kingdom of Saudi Arabia. The structure elucidation of the isolated natural products was based on extensive analysis of their spectroscopic data. Compounds 1&ndash, 6, 8, 10 and 11 were evaluated for their anti-inflammatory activity by quantifying nitric oxide (NO) release in response to TLR4 stimulation in macrophages. Besides compound 4 that did not exhibit any activity, all other tested metabolites inhibited NO production from activated macrophages. Among them, thyrsiferol (10) and 23-acetylthyrsiferol (11) displayed activity with IC50 values in the low nM scale without cytotoxicity.

Covering: 1957 to 2017 Algae constitute a heterogeneous group of eukaryotic photosynthetic organisms, mainly found in the marine environment. Algae produce numerous metabolites that help them cope with the harsh conditions of the marine environment. Because of their structural diversity and uniqueness, these molecules have recently gained a lot of interest for the identification of medicinally useful agents, including those with potential anticancer activities. In the current review, which is not a catalogue-based one, we first highlight the major biological events that lead to various types of cancer, including metastatic ones, to chemoresistance, thus to any types of current anticancer treatment relating to the use of chemotherapeutics. We then review algal metabolites for which scientific literature reports anticancer activity. Lastly, we focus on algal metabolites with promising anticancer activity based on their ability to target biological characteristics of cancer cells responsible for poor treatment outcomes. Thus, we highlight compounds that have, among others, one or more of the following characteristics: selectivity in reducing the proliferation of cancer cells over normal ones, potential for killing cancer cells through non-apoptotic signaling pathways, ability to circumvent MDR-related efflux pumps, and activity in vivo in relevant pre-clinical models.

The aim of the present study was the chemical analysis of the essential oils from Juniperus phoenicea and J. drupacea female cones and evaluation of their biological effects. Fresh samples, collected in Greece, were subjected separately to hydrodistillation and the oils obtained analyzed by GC-FID and GC-MS. The oils Were assessed using the CAM (chorioallantoic membrane) assay to evaluate their anti-angiogenic potential and the lack of irritant effects in topical application. GC analysis showed that mainly quantitative differences among the samples were observed: limonene was the most abundant compound in J. drupacea (27.0%) compared with J. phoenicea oil (1.6%); the content of a-pinene was high in both essential oils (J. phoenicea 22.1%, J. drpacea 26.1%) followed by germacrene D (J. phoenicea 7.4%, J. drpacea 7.1%, respectively). Nevertheless, qualitative differences were also detected as the diterpene 4-epi-abietal was present in a considerable amount (13.2%) in J. phoenicea essential oil, but was not detected in J. drupacea oil. In the CAM assay, only J. phoenicea. essential oil evidenced a rather weak anti-angiogenic activity compared with the standard retinoic acid, but no irritant effect was observed for either essential oil suggesting their safety for topical application.

Since the essential oil of Salvia sclarea is used as a flavouring agent, the effect of different extraction techniques (hydrodistillation & HS-SPME) and duration of hydrodistillation (2, 3 and 4 h) with respect to yield, composition and identification rate of extracted essential oils from Greek cultivated S. sclarea aerial blooming parts were investigated. Linalool and linalyl acetate levels seemed to decrease with increasing duration of hydrodistillation, while diterpenes increased dramatically, while the head space analysis showed significantly lower levels of linalool in comparison to its ester. Thus, linalool (5.1-35.8%), linalyl acetate (11.3-37.6%) and sclareol (0.0-41.8%), concerning the oils obtained by hydrodistillation, were the most important metabolites. Solid-phase microextraction yielded mainly oxygenated monoterpenes, especially linalyl acetate (59.3%), followed by cis-linalool oxide (8.6%) and linalool (7.8%).

Food, besides providing nutrients to satisfy the metabolic requirements, through various bioactive constituents modulates a number of functions in the body, thus playing detrimental or beneficial roles in a number of diseases. Seaweeds are rich in polysaccharides, proteins, minerals, vitamins, secondary metabolites, and polyunsaturated fatty acids, with low caloric value. Macroalgae, producing a great variety of bioactive compounds that have exhibited a wide spectrum of activities ranging from the treatment of allergies, diabetes, hypertension, oxidative stress, inflammation, thrombosis, obesity, and lipidemia to serious degenerative disorders and cancer, have a high potential as a source of functional ingredients. In this chapter, an overview of the most important bioactive seaweed constituents with their potential use in functional foods is presented.

Pines, usually tall and stout trees and less often shrubs, have evergreen foliage leaves in the shape of needles and contain resin in their bark. The techniques commonly applied for the assessment of the physicochemical properties of pine needle oil include the measurement of specific gravity, the determination of refractive index, and the measurement of optical rotation. There is an ancient belief that there is a relation between the pine needle oil and good health. This belief is based on its strong disinfectant and therapeutic properties. A parasite affected by pine needle oil is the nematode Bursaphelenchus xylophilus, which causes the pine wilt disease. The use of pine needle essential oils against human and agricultural pests and parasites has certain limitations relating to the toxicity of the oils and their inefficiency against a number of pest organisms.

The fresh needles of 46 pine species, including 37 and 17 taxa of the subgenera Pinus and Strobus, respectively, were subjected to hydrodistillation and the essential oils obtained were analyzed by means of GC–FID and GC–MS. The comprehensive analyses of the needle oils, which allowed for the identification of 161 constituents comprising the majority of the volatiles, showed significant, not only quantitative, but also qualitative differences between the samples. Monoterpenes, sesquiterpenes and diterpenes dominated the pine foliage oils, with the presence of the monoterpene hydrocarbons α- and β-pinene and the sesquiterpene hydrocarbon germacrene D characterizing most of the oils. This is the first report on the chemical composition of the essential oils of 21 pine taxa, including 15 taxa of subgenus Pinus and 6 taxa of subgenus Strobus.

Fresh leaves of Myrtus communis collected from different localities in Greece, were subjected to hydrodistillation and the oils obtained were analyzed by GC-FID and GC-MS. The analyses showed mainly quantitative differences, with the monoterpenes myrtenyl acetate, α-pinene, 1,8-cineole, and linalool, along with limonene, dominating the majority of the analyzed Myrtle oils. The evaluation of the larvicidal activity of the samples against Culex pipiens biotype molestus mosquito showed that all tested samples exhibited moderate to weak toxicity, with cultivated M. communis subsp. communis oil being the most active.

The aim of the present study was the chemical analysis of the essential oils from Juniperus phoenicea and J. drupacea female cones and evaluation of their biological effects. Fresh samples, collected in Greece, were subjected separately to hydrodistillation and the oils obtained analyzed by GC-FID and GC-MS. The oils were assessed using the CAM (chorioallantoic membrane) assay to evaluate their anti-angiogenic potential and the lack of irritant effects in topical application. GC analysis showed that mainly quantitative differences among the samples were observed: limonene was the most abundant compound in J. drupacea (27.0%) compared with J. phoenicea oil (1.6%); the content of α-pinene was high in both essential oils ( J. phoenicea 22.1%, J. drupacea 26.1%) followed by germacrene D ( J. phoenicea 7.4%, J. drupacea 7.1%, respectively). Nevertheless, qualitative differences were also detected as the diterpene 4- epi-abietal was present in a considerable amount (13.2%) in J. phoenicea essential oil, but was not detected in J. drupacea oil. In the CAM assay, only J. phoenicea essential oil evidenced a rather weak anti-angiogenic activity compared with the standard retinoic acid, but no irritant effect was observed for either essential oil suggesting their safety for topical application.

Dried aerial parts of five taxa of Greek Sideritis were subjected to hydrodistillation and the oils obtained were analyzed by using GC and GC-MS. A total of 82 compounds were identified and the analysis showed important differences between the samples not only quantitatively but also qualitatively. The microbial growth inhibitory properties of the essential oils were determined using the broth microdilution method against eight laboratory strains of bacteria - Gram positive: Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus luteus, Еnterococcus faecalis, Bacillus subtilis and Gram negative: Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, a nd two strains of the yeast Candida albicans. The tested essential oils exhibited considerable activity against certain strains of the microorganisms tested, with S. lanata oil presenting MIC values to S. aureus and M. luteus comparable to those of the reference antibiotics. .

The essential oils of Stachys spruneri Boiss. (sample A and sample B) were analyzed by GC and GC-MS. (+)-Isoabienol was the dominant component (49.5 and 48.2%, respectively of the total oils) among seventy-two identified constituents. Isoabienol was separated, purified by preparative thin-layer chromatography, and further identified by means of physicochemical and spectrometric analysis. The microbial growth inhibitory properties of the essential oil and its main metabolite, the labdane diterpene isoabienol, were determined using the broth microdilution method against eight laboratory strains of bacteria (Gram- positive: Staphylococcus aureus, S. epidermidis, Micrococcus luteus, Enterococcus faecalis, Bacillus subtilis, and Gram- negative: Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and two strains of the yeast Candida albicans. Both essential oil and isoabienol showed considerable activity against all the microorganisms tested, with the isolated compound being most active.

The essential oils from stems, leaves, inflorescences, and both unripe and ripe infructescences of Smyrnium olusatrum L. (Umbelliferae) collected in Greece were obtained by hydrodistillation and analyzed by GC-FID and GC-MS. Fifty-eight components were identified. Among the samples analyzed, the differences observed were mainly quantitative. All oils were characterized by the abundance of sesquiterpenes. The major components of the stem and leaf oils were furanoeremophil-1-one (54.3% and 28.7%, respectively) and curzerene (18.8%, 29.0%). The main constituents of the inflorescence oil were curzerene (38.1%), germacrone (20.2%) and furanoeremophil-1-one (20.0%), while those of the unripe and ripe infructescence oils were 1β-acetoxy-furanoeudesm-4(15)-ene (22.1%, 30.8%) and curzerene (29.7%, 17.4%).

Fresh leaves of Myrtus communis collected from different localities in Greece, were subjected to hydrodistillation and the oils obtained were analyzed by GC-FID and GC-MS. The analyses showed mainly quantitative differences, with the monoterpenes myrtenyl acetate, α-pinene, 1,8-cineole, and linalool, along with limonene, dominating the majority of the analyzed Myrtle oils. The evaluation of the larvicidal activity of the samples against Culex pipiens biotype molestus mosquito showed that all tested samples exhibited moderate to weak toxicity, with cultivated M. communis subsp. communis oil being the most active.