Essential oils from 11 Cannabis sativa cultivars isolated by different methods and toxicological evaluation of their components

Industrial hemp is grown for numerous applications, traditionally for the production of textile fiber, pressing oil from the seeds and in foods. More recently, non-psychotropic phytocannabinoids have attracted an increasing interest of researchers and medics due to their health benefits. Industrial hemp accumulates comparatively low amounts of essential oil (EO); however, it is considered as an important ingredient for some hemp oil based products. The aim of this study was to expand the existing knowledge on the composition of EO compounds isolated from eleven Cannabis sativa cultivars using Clevenger hydrodistillation and supercritical CO2 extraction (SFE-CO2) for their isolation. In addition, microwave (MAD) and ultrasound (UAD) assisted distillation has been tested in order to evaluate their advantages. The dried plant material was ground using a 0.5-mm hole size sieve before EO isolation, while the fresh material was used undried. MAD was applied to the fresh material without its dilution with water, while SFE-CO2 was performed in Helix extractor using 2 separators operating at different pressure and temperature. EO collecting vessel was cooled from -40 to +20 in order to evaluate possible losses of volatile constituents during system depressurization. The yield of EOs varied from 0.07 to 0.35% depending on the cultivar, extraction method, plant harvesting time, drying and SFE-CO2 parameters. The main volatile components identified and quantified in C. sativa cultivars by GC´GC-TOF/MS and GC-FID, respectively, were b-caryophyllene (16.6-34%), humulene (13.1-30.0%), a-pinene (0.1-31.2%), caryophyllene oxide (4.3-10.2%), b-pinene (0.1-8.3%), myrcene (0.2-9.5%), limonene (0.1-2.7%), eucalyptol (0.1-3.1%), humulene epoxide II (1.4-3.6%) and trans-b-farnesene (1.3-4.6%). The toxicology of the main EO components was reviewed based on the previously reported data. In the second part of this study acetone extracts of the solid residue and water extracts consisting of the liquid phase after hydrodistillation were used for evaluating their antioxidant activities and total phenolic content in order to assess the possibility of using plant distillation residues as a source of various functional non-volatile ingredients. It was recently reported that the biorefining approach may give several valuable fractions from hemp threshing residues [1]

Changes of photosynthetic pigments amount and colour of baby leaves lettuce during storage

Tyrimai atlikti Aleksandro Stulginskio universitete. Tirtos keturių veislių mažosios salotos: raudonlapės ‘Ovired’ ir ‘Redza’ bei žalialapės ‘Alanet’ ir ‘Lettony’. Salotos pasėtos 2015 m. gegužės 8 d., nuimtos – 2015 m. birželio 5 d. Laikytos šaldytuve 2 ± 0,5 °C temperatūroje esant 90 % santykiniam drėgniui 14 dienų. Laikomose salotose analizuoti fotosintetinių pigmentų kiekio ir spalvos pokyčiai. Spalvos pokyčiai įvertinti spektrofotometru nustačius L*a*b* koordinačių reikšmes NBS vienetais, o fotosintetinių pigmentų – ištyrus chlorofilo a ir b bei bendrą karotenoidų kiekį. Laikymo metu fotosintetinių pigmentų kiekis visų tirtųjų veislių mažųjų salotų lapuo­se keičiasi labai nežymiai. Keturiolika laikymo dienų nepaskatino salotų senėjimo proceso tiek, kad būtų nustatytas statistiškai esminis chlorofilo a skilimas, o chlorofilo b pokyčiai dar mažesni. Bendrasis karotenoidų kiekis statistiškai esminiai didėjo visų veislių, išskyrus ‘Ovired’, salotų lapuose. Spalva priklauso nuo genetinių salotų veislių savybių, tačiau laikymo metu kai kurie spalviniai komponentai skyla, ir maisto žaliavų spalva keičiasi. Laikant mažąsias salotas keičiasi jų L* koordinatės reikšmė, salotų lapai šviesėja, o žalialapių salotų lapų spalvos koordinatės b* reikšmė didėja (salotos gelsta)Research was carried out at Aleksandras Stulginskis University. Four varieties of baby leaves lettuce were investigated: ‘Ovired’, ‘Redza’, ‘Alanet’, and ‘Lettony’. Lettuce was stored for 14 days in a refrigerator at 2 ± 0.5 °C temperature and 90% relative humidity. Chlorophyls, total carotenoid contents, and lettuce colour were determined periodically during the storage. Amounts of photosynthetic pigments in baby leaves during the 14-day storing period in the refrigrator changed slightly. These metabolites changes can be more related with genetic properties of baby leaves than with storing conditions. Colour depends on lettuce genetic properties, but during storage destruction of colourful compounds can be observed and colour of raw agricultural products changes. The value of L* coordinate changes, lettuce leaves lighten, and the value of b* coordinate shows the yellowing of lettuce leavesVytauto Didžiojo universitetasŽemės ūkio akademij