Dried heartwood powder of Maclura pomifera, Moraceae, was extracted with acetone. Silica gel column chromatography (CC) of the crude extract yielded 2',3',4',5'-tetrahydroxystilbene (oxyresveratrol).

The employment of supercritical carbon dioxide extraction for obtaining the chemical compounds from N. tabacum leaves, especially nicotine, is advancing. The supercritical carbon dioxide extraction of dried N. tabacum cv. Samsun and N. tabacum cv. Virginia at different process parameters was performed to obtain the highest extraction yield and nicotine relative amount. The optimal extraction conditions concerning the highest extraction yield and nicotine relative amount were determined by response surface methodology. The highest extraction yield for N. tabacum cv. Samsun was 2.99% and for N. tabacum cv. Virginia 2.33% at 23.41 MPa, 50 °C and 90 min of extraction time. The highest nicotine relative amount in N. tabacum cv. Samsun and N. tabacum cv. Virginia was at 15 MPa, 50 °C and 90 min extraction time and was 242.1 mg per 100 g of plant material and 32.4 mg per 100 g of plant material, respectively. The pressure, temperature and time influenced the extraction yield and nicotine relative amount recovery in N. tabacum cv. Samsun and N. tabacum cv. Virginia. A general inclusive concept in respect to pressure, temperature and time of the supercritical carbon dioxide extraction and a report on phytochemicals present in two N. tabacum varieties is presented.

Chlorophyll catabolism in Prunus serrulata autumnal leaves was investigated. The amount of chlorophyll catabolites accumulated within the same plant species varies with the time of the leaf collection, seasonal climate and developmental stage of the plant. The chlorophyll catabolites found in P. serrulata autumnal leaves presented the tendency of the organism to decrease the level of photodynamically active chlorophyll before the programmed cell death. In the methanol extract several chlorophyll catabolites were identified. The results obtained by liquid - chromatography/mass spectrometry permitted the identification of the chlorophyll catabolites found in P. serrulata autumnal leaves. The analysis done revealed the chlorophyll catabolic pathway found in P. serrulata autumnal leaves

No abstract

Supercritical carbon dioxide extraction was used for the extraction of Parrotia persica yellow and amber leaves. The lipophilic phytochemicals present in the analyzed leaves were as follows: neophytadiene, hexahydrofarnesyl acetone, octadecanal, 1-octadecanol, phytol, squalene and α-tocopherol. α-cadinol was present in yellow and β-sitosterol in amber leaves. The Box–Behnken design was used for the optimization of pressure, temperature and CO2 flow rate and response surface methodology for the total extraction yield and α-tocopherol relative amount. The total extraction yield was 1.62% for yellow and 1.52% for amber leaves. The α-tocopherol relative amount was 80.03 mg per 100 g of dry plant material for yellow leaves and 315.30 mg per 100 g of dry plant material for amber leaves. The effects of temperature and CO2 flow rate were found to have a significant influence on the total extraction yield for both plant materials analyzed. The effects of pressure and temperature significantly influenced the α-tocopherol relative amount in both plant materials used. The optimum extraction conditions for the total extraction yield were 30 MPa, 40 °C and 3 kg·h−1 CO2 flow rate for both plant samples. In the case of the α-tocopherol relative amount, the optimum temperature was 40 °C, while the pressure and CO2 flow rate were slightly different. The predicted values matched well with the experimental values for the total extraction yield and α-tocopherol relative amount in all plant materials used for the experiment.