Rising levels of greenhouse gases (GHG) in our atmosphere make it necessary to find pathways to reduce the amount of GHG, especially emissions of CO2. One approach is carbon capture and utilization ...by mineralization (CCUM). With this technology, it is possible to bind CO2 chemically from exhaust gas streams in magnesium or calcium silicates. Stable products of this exothermic reaction are carbonates and amorphous silica. Being amongst the biggest emitters of CO2, the cement industry has to find ways to reduce emissions. Geological mapping in Europe has been carried out to find suitable feedstock material, mainly olivines but also slags, to perform lab‑scale carbonation tests. These tests, conducted in a 1.5 L autoclave with increased pressure and temperature, have been scaled up to a 10 L and a 1000 L autoclave. The outcomes of the carbonation are unreacted feed material, carbonate, and amorphous silica, which have to be separated to produce substitutes for the cement industry as pozzolanic material (amorphous silica) or a value‑added product for other applications like paper or plastics (magnesite/calcite with bound anthropogenic CO2). Therefore, a process for the separation of ultrafine carbonation product was developed, consisting mainly of classification and flotation.
In this study, free volatile compounds (FVCs) were isolated from the water fractions (hydrosols) of 10 Croatian Veronica species obtained by hydrodistillation (HD) and microwave-assisted extraction ...(MAE). The use of different isolation techniques is important for the analysis of the influence of extraction conditions on the qualitative and quantitative composition of the isolated constituents. The composition of the hydrosols was analyzed using gas chromatography and mass spectrometry. The compounds β-ionone and benzene acetaldehyde were detected in all 10 Veronica hydrosols studied. E-caryophyllene was also identified in all isolates except the MAE isolate of V. arvensis L. Caryophyllene oxide was isolated in all isolates apart from the HD isolate of V. catenata Pennell. (E)-β-Damascenone is significantly present in all isolates except the MAE isolates of V. catanata and V. cymbalaria Bodard. In these two species, α-muurolol was identified in a high percentage. The same basic phytochemical constituents and compounds characteristic of a given Veronica species suggest the importance of further research. Antioxidant activity was tested for all extracts using two methods, ORAC and DPPH. Therefore, it is crucial to identify as many specialized metabolites from Veronica species as possible, especially hydrosols, which are natural products of potential pharmacological interest.
The present results dealing with the antiphytoviral activity of essential oil indicate that these plant metabolites can trigger a response to viral infection. The essential oil from
and the main oil ...components β-caryophyllene and caryophyllene oxide were tested for antiphytoviral activity on plants infected with satellite RNA associated cucumber mosaic virus. Simultaneous inoculation of virus with essential oil or with the dominant components of oil, and the treatment of plants prior to virus inoculation, resulted in a reduction of virus infection in the local and systemic host plants. Treatment with essential oil changed the level of alternative oxidase gene expression in infected Arabidopsis plants indicating a connection between the essential oil treatment,
gene expression and the development of viral infection.
Since the aetiology of benign prostatic hyperplasia (BHP) is still unknown, the use of medicinal herb extracts and products prepared thereof are recommended due to their antimicrobial activity, ...especially during early stages of BHP. A comparison was performed of the in vitro antimicrobial activity (using broth microdilution assay) of flowers and leaves of willowherb (Epilobium angustifolium L., Onagraceae) from Mt. Velebit (Croatia). The strains (standard ATCC and clinical isolates) of Staphylococcus aureus (including MRSA), Bacillus subtilis, Escherichia coli (including p-fimbriae positive strain), Pseudomonas aeruginosa, Proteus mirabilis, Candida albicans, C. tropicalis, C. dubliniensis and Saccharomyces cerevisiae were susceptible with MIC values between 4.6±0.2 and 18.2±0.8 mg/mL. The results of in vitro studies showed that no differences were found in the antimicrobial activity between the ethanol extracts of leaves and flowers of E. angustifolium. Using the quantitative fluorescent assay with ethidium bromide and acridine orange, the viability of C. albicans ATCC 10231 was assessed after in vitro exposure to E. angustifolium leaf and flower ethanol extracts. Apoptosis of C. albicans blastospores dominated over necrosis in all treated samples after short-term exposure with 6 to 12 mg/mL of extracts. In addition to the valuable biological activity of E. angustifolium extracts, the data obtained from the in vitro diffusion, the dilution assay and antifungal viability fluorescent assay suggest that leaf and flower ethanol extracts of E. angustifolium L. are a promising complementary herbal therapy of conditions such as BHP.
This work investigates the possible mineral input materials for the process of mineral sequestration through the carbonation of magnesium or calcium silicates under high pressure and high ...temperatures in an autoclave. The choice of input materials that are covered by this study represents more than 50% of the global peridotite production. Reaction products are amorphous silica and magnesite or calcite, respectively. Potential sources of magnesium silicate containing materials in Europe have been investigated in regards to their availability and capability for the process and their harmlessness concerning asbestos content. Therefore, characterization by X-ray fluorescence (XRF), X-ray diffraction (XRD), and QEMSCAN® was performed to gather information before the selection of specific material for the mineral sequestration. The objective of the following carbonation is the storage of a maximum amount of CO2 and the utilization of products as pozzolanic material or as fillers for the cement industry, which substantially contributes to anthropogenic CO2 emissions. The characterization of the potential mineral resources for mineral sequestration in Europe with a focus on the forsterite content led to a selection of specific input materials for the carbonation tests. The mineralogical analysis of an Italian olivine sample before and after the carbonation process states the reasons for the performed evaluation. The given data serves as an example of the input material suitability of all the collected mineral samples. Additionally, the possible conversion of natural asbestos occurring in minerals as a side effect of the carbonation process is taken into consideration.
Extracts from Veronica species (speedwells) are known for the various biological activities they show, such as cytotoxic, antimicrobial, anti-inflammatory, and antioxidant activities. Also, the ...plants from this genus are known as medicinal plants used in traditional medicine worldwide. Phenolic compounds are specialized metabolites that contribute to biological activity the most. Therefore, the aim of this research is identification and quantification of phenolic compounds present in three Veronica species (Veronica anagallis-aquatica L., Veronica persica Poir., and Veronica polita Fr.) using the liquid chromatography-mass spectrometry (LC-MS/MS) technique. All extracts were tested for antioxidant activity with two methods: DPPH (2,2-diphenyl-1-picrylhydrazyl) and ORAC (oxygen radical absorbance capacity). Also, standards for compounds that were detected in the highest amount in all species were also tested for antioxidant activity. Three different solvents (pure methanol, 80% ethanol, and water) were used for the extraction of phenolic components and their comparison in order to test their antioxidant activity as a final goal. The main compounds present in the tested Veronica extracts were: p-hydroxybenzoic acid, vanillic acid, caffeic acid, gentisic acid, and apigenin. V. anagallis-aquatica contained the highest amount of phenolic components in comparison with the two other tested species, V. persica and V. polita. Caffeic acid showed the highest antioxidant activity in both studied methods with an IC50 value for DPPH activity of 1.99 µg/mL. For the plant extracts, in general, methanolic/ethanolic extracts showed higher activity than water extracts in both methods which was expected, as organic solutions extract more phenolic compounds. This research points to the potential application of extracts of different Veronica species for antioxidant activity.
Farmaceutski botanički vrt ''Fran Kušan'' Farmaceutsko-biokemijskog fakulteta Sveučilišta u Zagrebu osnovan je 1946. godine i danas je jedan od tri sveučilišna botanička vrta u Hrvatskoj. O biljnom ...fondu Vrta ima vrlo malo objavljenih podataka te je s tim ciljem provedena inventarizacija drvenastih svojti koje rastu u arboretumu Vrta kao i u dva staklenika. Pri tome je utvrđeno da u arboretumu Vrta danas raste 457 svojti od kojih je 359 ljekovito, a 152 otrovne. U dva staklenika uzgajaju se još 62 drvenaste svojte toplijih klimata od kojih je 48 ljekovito, a 11 otrovno.
he Pharmaceutical Botanical Garden "Fran Kušan" of the Faculty of Pharmacy and Biochemistry of the University of Zagreb was founded in 1946 and today it is one of three university botanical gardens in Croatia. There is a little published information about the Garden's plant collection, and with this aim, an inventory of woody taxa growing in the Garden's arboretum and two greenhouses was carried out. It was found that 457 taxa grow in the arboretum of the Garden today, of which 359 are medicinal and 152 are poisonous. Another 62 woody taxa from warmer climates are grown in two greenhouses of the Garden, of which 48 are medicinal and 11 are poisonous.
The composition of the essential oil depends on the duration and conditions under which the distillation of the plant material is carried out. In this study, one sample without fractionation and ...eight fractions (each after 15 min of steam distillation) of the essential oil of cultivated H. italicum were analysed by gas chromatography-mass spectrometry (GC-MS). The steam conditions for all samples were as follows: flow rate 800 L/h, temperature 104 °C, and pressure 0.4 bar. The test of the antimicrobial activity was performed with the modified Kirby–Bauer method (disc diffusion method) on non-selective nutrient media (blood agar) using the reference bacterial and fungal strains. A total of 75 different components were found in the essential oil samples obtained. A shorter distillation time makes the oil richer in monoterpenes and more suitable for the perfume and cosmetics industry. On the other hand, prolonged distillation leads to the essential oil being enriched with sesquiterpene oxides, which can have a negative effect on the fragrance of the essential oil. The essential oil of H. italicum showed antimicrobial activity only against Staphylococcus aureus ATCC 25923, and the best activity was shown by the sixth fraction.
Vanadium has been strongly moving into focus in the last decade. Due to its chemical properties, vanadium is vital for applications in the upcoming renewable energy revolution as well as usage in ...special alloys. The uprising demand forces the industry to consider the exploration of less attractive sources besides vanadiferous titanomagnetite deposits, such as lead vanadate deposits. Mineral processing and metallurgical treatment of lead vanadate deposits stopped in the 1980s, although the deposits contain a noteworthy amount of the desired resource vanadium. There has been a wide variety of research activities in the first half of the last century, including density sorting and flotation to recover concentrates as well as pyro- and hydrometallurgical treatment to produce vanadium oxide. There have been ecological issues and technical restrictions in the past that made these deposits uninteresting. Meanwhile, regarding the development of mineral processing and metallurgy, there are methods and strategies to reconsider lead vanadates as a highly-potential vanadium resource. This review does not merely provide an overview of lead vanadate sources and the challenges in previous mechanical and metallurgical processing activities, but shows opportunities to ensure vanadium production out of primary sources in the future.
Strawberry tree (Arbutus unedo L.) leaves are used in folk medicine for treating inflammation, hypertension, and diabetes. The aims of this study were to evaluate the antimicrobial effects of A. ...unedo leaf extracts on 15 uropathogens and test the extent to which arbutin, as the most abundant bioactive compound in the leaves, is responsible for their antimicrobial activity. Antimicrobial activity of leaf extracts against urinary pathogenic microorganisms was tested by agar well diffusion assay and twofolded microdilution method. Since the polyphenolic content responsible for A. unedo leaves’ antimicrobial activity depends on climate and geolocation, the authors determined the total phenolic, tannin, flavonoid and phenolic acid content using spectrophotometric methods, arbutin and hydroquinone mass fraction using high performance liquid chromatography coupled with a diode array detector (HPLC–DAD) and antioxidative activities by FRAP, ABTS, and DPPH assay. Although methanol was shown to be a more effective solvent for the extraction of polyphenols from leaves, the traditionally used aqueous extract exhibited similar antimicrobial properties. While arbutin did not show direct antimicrobial activity, its metabolite hydroquinone showed strong antimicrobial activity against the tested uropathogens. The strongest antimicrobial activity of leaf extracts was detected for uropathogenic strains of Enterococcus faecalis, which was probably associated with the ability of bacterial β-glucosidase, exerting strong activity in E. faecalis, to convert arbutin to hydroquinone. Our study suggested that the aqueous extract of strawberry tree leaves has the potential for use as a phytotherapeutic in clinical application and should be further investigated.
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