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Iris lutescens is a rhizomatous species of the Iridaceae family, generally found in the dry areas of the Mediterranean basin. It is characterised by large flowers, exhibiting a colour polymorphism in two varieties (yellow and purple). Even though it can grow on calcareous soils, it is reported as a serpentine-preferential taxon. In this work, the volatile emission in the headspaces of flowers, leaves and rhizomes of specimens of both the colour morphs growing on an ultramafic garigue have been analysed. The flower and rhizome headspaces had greater overall similarities compared to the leaves; flowers were the organs for which the volatile emission differed the most between the two colour morphs. Moreover, a comparison with a published headspace composition of I. lutescens yellow and purple flowers growing on calcareous soil evidenced quali-quantitative differences, as well as a greater differentiation of the volatile organic compounds emitted by the two colour morphs growing in a serpentine environment. To the best of our knowledge, this is the first report on the volatile emission of different organs of I. lutescens specimens growing on serpentine soil. [ABSTRACT FROM AUTHOR]

The essential oil was obtained by separate hydrodistillation from the aerial parts of Carduncellus pinnatus (Desf.) DC. (Asteraceae) and was analyzed by means of gas chromatography (GC) and gas chromatography–mass spectrometry (GC-MS). Hundred and four compounds were detected, accounting for 95.29 % of the total oil, which is characterized by a high content of non-terpene derivatives (33.39%) and oxygenated sesquiterpenes (32.03%). The main constituents of the essential oil from the aerial parts were caryophyllene oxide (23.12%), (E)-2-hexenal (8.35%), (E)-β-ionone (6.01%), (E)-geranylacetone (2.96%), and nonanal (2.65%). Additionally, β-Carotene-linoleic acid test system, DPPH free radical scavenging assay and ABTS cation radical scavenging assay were tested for the study of antioxidant activity of plant methanol extract and essential oil. The MeOH extract of aerial parts exhibited a strong antioxidant activity evidenced by the ABTS cation radical scavenging assay, with IC50 values of 44.509 ± 1.149 µg/ml. In the DPPH test the IC50 values were 61.147 ± 0.924µg/ml, while in β-carotene-linoleic acid test system, the IC50 values were 153.744 ± 3.39µg/ml. Essential oil extract of aerial parts showed 81.80 ℅ inhibition against butyrylcholinesterase at 200 µg/mL. The highest antibacterial activity was evidenced for the aerial parts MeOH extracts, with inhibition zone medium diameters of 18.66±1.00 mm against Escherichiacoli ATCC25922 at 16 mg/ml and of and 18.00±1.15mm against Micrococcus luteus ATCC533 at 16 mg/ml. This is the first report about the potential for food and pharmaceutical industry due to the composition and the biological activities of Carduncellus pinnatus essential oils growing in Algeria. [ABSTRACT FROM AUTHOR]

Cleome amblyocarpa Barr. and Murb is a medicinal plant widespread in North Africa and widely used in Tunisia to treat diabetes and colic. The non-volatile (polyphenols, flavonoids, tannins, and flavonols) and volatile compounds (GC-MS) of C. amblyocarpa leaves and stems have been studied. The antioxidant, antimicrobial, analgesic, and cytotoxic activities of hydroalcoholic extracts of C. amblyocarpa leaves and stems were also investigated. The major volatile components were β-caryophyllene (46.9%), eugenol (25.6%), ethyl 3-methylpentanoate (16.2%), 7-epi-silphiperfol-5-ene (11.0%), and α-copaene (7.0%). The antioxidant activity has been evaluated using various in vitro assays, such as DPPH free radical scavenging activity, iron-chelating capability, and ability to inhibit lipid peroxidation (TBARS). The antibacterial and antifungal effectiveness of leaves and stems parts of Cleome amblyocarpa were investigated by means of the disc diffusion and microdilution techniques. The in vitro cytotoxicity of the hydroalcoholic extract of C. amblyocarpa on A549 and H1299 lung adenocarcinoma cells was determined using the crystal violet assay. The acute toxicity of the extracts on Swiss albino mice at the doses of 3000, 1500, and 500 mg/kg body weight was evaluated. The analgesic effect of leaves and stems extract was also determined by means of the acetic acid induced writhing test. The results indicated that the leaves have higher phenols, and flavonoids contents and potential antioxidant, antimicrobial, and anticancer activities in comparison to stem. In addition, the aerial part of C. amblyocarpa did not cause signs of toxicity or death in animals at doses up to 3000 mg/kg and have a significant analgesic activity. [ABSTRACT FROM AUTHOR]

• Mutualistic interactions in pollination networks depend on the conservation of both pollinator and wildflower communities. • The botanical complexity of wildflower strips leads to a prolonged food availability for pollinators. • Some wildflower species were visited by a wide range of pollinators, while others were more selective. • The predominance of a chemical class of volatile implies the attraction for specific pollinators. • The choice of species in wildflower strips leads to differences in performance: diversified flowering periods and/or diversified attractiveness to pollinator species. The intensification of agricultural practices contributes to the decline of many taxa, such as insects and weeds. Wildflower species have an important environmental impact on rural biodiversity since plant-pollinator networks play a key role in both landscape aesthetics and environmental functionality. Due to their scarcity and/or disappearance in conventional agroecosystems, wildflowers are now being used in strips to restore the agro-environment. In this study, fifteen wildflower species were sown in order to verify their ecological performance in terms of a plant-pollinator interaction while in laboratory the several chemicals emitted by the flowers were identified. Flowering periods were concentrated in the spring, although flowering periods extended to the hot and dry summer months in some species. An extreme variability was found in terms of quantitative and qualitative pollinator-attractiveness (i.e., bees, bumblebees, hoverfly, bee flies and butterflies). Most wildflower species emit a volatiles belonging above all to one of the several chemical classes. A hierarchical cluster analysis of the different volatile emissions did not fully correlate with the botanical taxa of the respectives wildflowers. Often, single chemical compounds prevailed, such as β-ocimene and limonene among monoterpenes hydrocarbons, santolina alcohol in the case of oxygenated monoterpenes, or (Z) - or (E) -3-hexenol acetate for non-terpenes derivatives. It is believed that these chemical compounds can play an ecological role in plant-pollinator food webs. The hypothesis that the chemistry of the volatiles implies a specialized plant-pollinator co-evolution was confirmed by a significant regression (p < 0.05), which showed an inverse relationship between chemical diversity (H') and pollinator dominance (D) indexes. The chemical specificity indicates the specificity of pollinators and vice versa. [ABSTRACT FROM AUTHOR]

Several aroma hops (Humulus lupulus L.) were recently introduced in Northern Italy as a small-scale production of excellence. In this preliminary study, the American cultivar Cascade was investigated in a combined morphological and phytochemical survey. Morphological investigation on trichome structure, density and distribution was performed by scanning electron microscopy and light microscopy. Essential oil composition, α/β-acid and polyphenol profiles over 3 years were determined by GC-MS and HPLC analyses. Two types of non-glandular (simple and cystolithic) and glandular (peltate and bulbous) trichomes were observed on leaves and female inflorescences. The peltate trichomes resulted as the main sites of terpene production and accumulation. The essential oil profiles showed myrcene, β-caryophyllene, (E)-β-farnesene and humulene epoxide II as the dominant compounds over the three collection times, although with different relative abundances. The presence of two exclusive compounds, γ-muurolene and trans-γ-cadinene, characterized the investigated cv. Cascade, potentially enhancing herbal, woody and spicy aroma traits of this cultivation in Northern Italy. The bitter acid composition showed quantitative values consistent with literature data only for the second and third monitoring year. Qualitative differences in polyphenol content were also recorded, for the presence of quercetin-3-O-malonylglucoside and kaempferol-3-O-rutinoside, which may characterize this peculiar Italian cultivation. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate the polyphenolic and flavonoid contents in the leaves extracts of Ruscus hypophyllum. Antioxidant activity was estimated by α,α-diphenyl-β-picrylhydrazyl (DPPH) and 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS) assays. The anticoagulant activity of Ruscus extracts was evaluated in vitro, using the prothrombin time (PT) and a PTT-activated partial thromboplastin time tests. The antibacterial activity was tested against large number of important medically and resistant bacteria by the broth dilution method. In this study, ethyl acetate and chloroform extracts displayed the highest total phenols contents (74.76 mg EAG/g and 73.89 mg EAG/g, respectively) and flavonoid content 40 and 32.43 mg EC/g, respectively. The GC-MS analysis of ethyl acetate extract confirmed the presence of oxygenated sesquiterpenes and hydrocarbon diterpenes with percentages of 16.41% and 10.72%, respectively, but chloroform extract was rich with, oxygenated monoterpenes, and oxygenated diterpenes, with percentages of 6.19 and 3.27%, respectively. Among tested extracts, ethyl acetate exhibited the best antioxidant and anticoagulant activities. Furthermore, ethyl acetate and chloroform extracts showed important antibacterial activity against resistant bacteria methicillin-resistant Staphylococcus aureus (SARM), Acinetobacter imipenem-resistant (IMP/R), P. aeruginosa imipenem-resistant (IMP/R) and extended-spectrum beta-lactamase producing E. cloacae (BLSE) with minimal inhibitory concentration (MIC) values varying between 0.125 and 0.5 mg/mL. [ABSTRACT FROM AUTHOR]

The essential oils of the aerial parts and roots (APEO and REO) of Pulicaria vulgaris subsp. dentata (Sm.) Batt. were analyzed by GC and GC-MS. Twenty-one compounds (97.2% of the total oil composition) were identified in the REO, with γ-irone (39.2%), 7-epi-silphiperfol-5-ene (19.3%), 2,5-dimethoxy-p-cymene (8.5%) and γ-himachalene (8.0%) as main constituents. The APEO was rich in cis-β-guaiene (59.7%), together with eighteen other compounds, accounting for 93.2% of the total oil composition. Antiradical and enzymatic antioxidant properties of the isolated oils were also evaluated. The REO exhibited the highest antioxidant activity using DPPH, ABTS, catalase and paraoxonase tests. Antimicrobial, cytotoxic and tyrosinase inhibiting properties of these essential oils have been also studied. APEO exhibited significant activity towards Pseudomonas syringae and Agrobacterium tumefaciens. The REO showed the most significant cytotoxic effect against HeLa cell line and the highest tyrosinase inhibition activity. [ABSTRACT FROM AUTHOR]

As one of the last places where coffee grows spontaneously, the Harenna forest (Ethiopia) is the origin of the coffee analysed in this study. The analysis of the volatile emission of each processing phase evaluates the chemical fingerprint of the reactions taking place at each stage, leading to the final aroma. The green beans mainly emit non-terpene esters and alkanes. Once the roasting begins, monoterpenes are the main class until 160 °C: at this point, 2,6-dimethylpyrazine prevails in the headspaces, as main product of the Maillard reactions. This compound, with its sweet and nut-like aroma, is also detected in the brewed coffee. The shed silverskins are rich in methyl chavicol and retain the monoterpenes on the beans: as these compounds are important aroma contributors, the removal of the silverskins prior to roasting seems non-advisable. The grinding of the samples breaks the matrices and leads to drastic changes in the volatile emissions. [ABSTRACT FROM AUTHOR]

Main conclusion: Volatile emissions were detected for the first time in male flowers of the early-branching angiosperm Amborella trichopoda, suggesting a defensive and attractive double role of these compounds. Flower volatile emissions were detected for the first time in male flowers of the early-branching angiosperm Amborella trichopoda. A mixture of seven volatile compounds is found in flower buds, with limonene resulting as the most abundant compound (67%). Further five volatiles are found in freshly opened flowers, with limonene contributing to 31.7%, followed by decanal (15.5%) and by ethyl octanoate (10.3%). While monoterpene hydrocarbons dominate in flower buds (73.6%), their emission in freshly opened flowers is reduced to 41.1%, while non-terpene derivatives are the most abundant (47.1%) chemical class. These compounds, emitted in low amounts, are possibly linked to pollen, which is considered the only reward offered for insect-pollination in this species. [ABSTRACT FROM AUTHOR]

Main conclusion: Salinity alters VOC profile in emitter sweet basil plants. Airborne signals by emitter plants promote earlier flowering of receivers and increase their reproductive success under salinity. Airborne signals can prime neighboring plants against pathogen and/or herbivore attacks, whilst little is known about the possibility that volatile organic compounds (VOCs) emitted by stressed plants alert neighboring plants against abiotic stressors. Salt stress (50 mM NaCl) was imposed on Ocimum basilicum L. plants (emitters, namely NaCl), and a putative alerting-priming interaction was tested on neighboring basil plants (receivers, namely NaCl-S). Compared with the receivers, the NaCl plants exhibited reduced biomass, lower photosynthesis, and changes in the VOC profile, which are common early responses of plants to salinity. In contrast, NaCl-S plants had physiological parameters similar to those of nonsalted plants (C), but exhibited a different VOC fingerprint, which overlapped, for most compounds, with that of emitters. NaCl-S plants exposed later to NaCl treatment (namely NaCl-S + NaCl) exhibited changes in the VOC profile, earlier plant senescence, earlier flowering, and higher seed yield than C + NaCl plants. This experiment offers the evidence that (1) NaCl-triggered VOCs promote metabolic changes in NaCl-S plants, which, finally, increase reproductive success and (2) the differences in VOC profiles observed between emitters and receivers subjected to salinity raise the question whether the receivers are able to “propagate” the warning signal triggered by VOCs in neighboring companions. [ABSTRACT FROM AUTHOR]