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Antioxidant properties of marjoram (Origanum majorana L.) herb and extracts obtained with ethanol, n-hexane, and supercritical CO2 extraction are presented. Individual antioxidants, ursolic acid, carnosic acid, and carnosol, were quantified with high-performance liquid chromatography. The effects of different parameters (temperature and pressure) of high-pressure extraction on the yield of carnosol were studied. Furthermore, two marjoram herbs from Hungary and Egypt were compared measuring hydrogen-donating abilities with 1,1-diphenyl-2-picrylhydrazyl by spectrophotometric and the total scavenger capacities by chemiluminometric methods from the aqueous extracts of the herbs. The antioxidant activities of the solvent extracts were performed using the Rancimat method. The Egyptian herb and its extracts possessed better antioxidant activities than Hungarian ones. Applying supercritical CO2 extraction, the highest value of carnosol was obtained at 400 bar and 60 degrees C.

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ABSTRACT:The ATPase assay using membrane preparations from recombinant baculovirus-infected Spodoptera frugiperda ovarian (Sf9) cells is widely used to detect the interaction of compounds with different ATP-binding cassette transporters. However, Sf9 membrane preparations containing the wild-type ABCG2 transporter show an elevated baseline vanadate-sensitive ATPase activity, which cannot be further stimulated by substrates of ABCG2. Therefore, this assay system cannot be used for the detection of ABCG2 substrates. To overcome this difficulty we 1) purified membranes from a selected human cell line expressing wild-type ABCG2, and 2) inhibited the baseline ATPase activity with different inhibitors. In our modified assay, ABCG2 substrates were able to stimulate the baseline ATPase activity of ABCG2 expressed in membranes of human cells. Furthermore, using the specific ABCG2 inhibitors Ko143 or Ko134 allowed us to suppress the baseline vanadate-sensitive ATPase activity. Substrates of ABCG2 could stimulate this suppressed baseline ATPase, resulting in a better signal-to-background ratio and a robust assay to detect substrates of the ABCG2 transporter. The ATPase assay and the direct vesicular transport measurements for estrone-3-sulfate were in good accordance.

Extraction of pigments (chlorophylls and carotenoids) from marjoram (Origanum majorana L.) with supercritical carbon dioxide was investigated. The aim of this study was to map the effects of extraction pressure and temperature on the yield of coloring materials by applying a 3(2) full factorial design with three repeated tests in the center of the design. For comparison, laboratory and pilot plant Soxhlet extractions were carried out using ethanol and n-hexane solvents. The compositions of pigments in marjoram extracts were determined by HPLC. Similar amounts of carotenoids, in addition to 40% of chlorophylls and their derivatives, were recovered from the supercritical fluid extraction, in comparison to the ethanol Soxhlet extraction.

Obtaining phytocannabinoids, associated with various medicinal and therapeutic properties with no reported side effects, is one of the hot topics. The phychotropic Δ 9 -tetrahydrocannabinol (THC) is less than 0.2 % in industrial cultivars therefore can be grown legally in many EU countries. Harvesting and processing of hemp for fiber or seeds generates large amount of wastes containing substantial amounts of bioactives such as cannabidiol (CBD) which are the primary cannabinoids along with cannabidiolic acid (CBDA), cannabinol (CBN), cannabigerol (CBG), and cannabichromene (CBC).The aim of this work was to optimize the extraction of cannabinoids from industrial hemp threshing residue using supercritical carbon dioxide extraction in pilot scales. The effects of extraction pressure and temperature on the extraction yield were evaluated. Three ground and pelleted samples of the same type but with different harvesting time were also compared. After derivatization of the samples the cannabinoids and the minor THCs were quantified by GC-MS. The extraction yields were between 0.2 -6.59 g/100 g dry mass depending on the source of hemp residue and on the process parameters of the extraction process. By increasing the pressure of extraction (in the range of 25-45 MPa at 45 °C) the extraction yields increased, meanwhile the yields of cannabinoids showed no significant increase. The volatile compounds were successfully separated from the cannabinoids with fractionated separation. From hemp threshing residues essential oil free extracts with high content of cannabinoids were obtained at 35 MPa extraction pressure and 45 °C temperature setting the first separator at 8 MPa and 40 °C.

Active components with antioxidant activity were extracted from the powder of pomegranate peel and added to polyethylene at 1000 ppm. The stabilization effect of the extract was studied also in compounds containing a phosphorous secondary antioxidant. A commercial hindered phenolic antioxidant with and without a secondary stabilizer was used as reference. The polymer was processed in multiple extrusions, and its functional group content, processability, residual stability, and color were determined by Fourier‐transform infrared (FTIR) spectroscopy, melt flow rate (MFR), and oxidation induction time (OIT) measurements as well as by the determination of the yellowness index. The pomegranate peel extract (POM) has very strong melt stabilization effect, which is comparable or better than that of the commercial hindered phenolic antioxidant used as reference. The extract hinders the reactions of the unsaturated groups of the polymer and prevents the formation of long‐chain branches. Similar to the phenolic antioxidant, it hinders also oxidation, thus preventing the formation of carbonyl groups. On the other hand, the extract does not offer sufficient residual stability and the polymer stabilized with it cannot be used in long‐term applications. The extract discolors the polymer somewhat that further limits its application possibilities. The contradiction of excellent processing stabilization and poor residual stability needs further study and explanation.