Study of the Size Distribution of Sulfur, Vanadium, and Nickel Compounds in Four Crude Oils and Their Distillation Cuts by Gel Permeation Chromatography Inductively Coupled Plasma High-Resolution Mass Spectrometry

The size distribution of sulfur, vanadium, and nickel was determined for four crude oils and their distillation cuts using gel permeation chromatography (GPC) coupled to inductively coupled plasma high-resolution mass spectrometry (ICP HR MS). The results show a trimodal distribution of vanadium and nickel compounds in the crude oils, the atmospheric residues, and the vacuum residues and, for sulfur compounds, either a mono- or bimodal distribution depending upon the distillation cut considered. A correlation exists between the sulfur fraction retention times and the temperature cuts of the distillation for a temperature below 560 °C and also between the viscosity of the crude oils and the proportion of trapped sulfur compounds in a higher boiling temperature fraction. The thermic treatment applied for the distillation increases the aggregation of low- and medium-molecular-weight compounds of vanadium and nickel into higher molecular weight aggregates between the crude oil on the one hand and the atmospheric residue and vacuum residue on the other hand, especially when the crude oil has a high total sulfur content

Increased synthesis of a new oleanane-type saponin in hairy roots of marigold (<i>Calendula officinalis</i>) after treatment with jasmonic acid

<p>Native plant of marigold (<i>Calendula officinalis</i> L.) synthesizes oleanolic acid saponins classified as glucosides or glucuronides according to the first residue in sugar chain bound to C-3 hydroxyl group. Hairy root culture, obtained by transformation with <i>Agrobacterium rhizogenes</i> strain 15834, exhibit a potent ability of synthesis of oleanolic acid glycosides. The HPLC profile of saponin fraction obtained from <i>C</i>. <i>officinalis</i> hairy roots treated with plant stress hormone, jasmonic acid, showed the 10-times increase of the content of one particular compound, determined by NMR and MALDI TOF as a new bisdesmoside saponin, 3-<i>O</i>-β-d-glucuronopyranosyl-28-<i>O</i>-β-d-galactopyranosyl-oleanolic acid. Such a diglycoside does not occur in native <i>C. officinalis</i> plant<i>.</i> It is a glucuronide, whereas in the native plant glucuronides are mainly accumulated in flowers, while glucosides are the most abundant saponins in roots. Thus, our results revealed that the pathways of saponin biosynthesis, particularly reactions of glycosylation, are altered in <i>C. officinalis</i> hairy root culture.</p