Essential oils from many plants are known to exhibit antimicrobial activity that can act as a chemical protectant against pathogenic plant diseases [1,2]. Essential oils (EO) from carrot seeds contain biologically active compounds [3,4] and, although their biological activity has been known for a long time, the chemical composition and biological activity of essential oil from seeds of carrots growing in Uzbekistan have not yet been studied.Commercially available carrot seeds (Daucus carota sativa, 100 g) were extracted for 4 h by steam distillation. The amber-colored essential oil was separated from water by ether and dried overnight over anhydrous Na 2 SO 4 to afford essential oil in 2.2% yield.The chemical composition of EO was studied by GC/MS on a Perkin-Elmer Turbo Mass Aid System XL gas chromatograph with a quadrupole mass spectrometer as the detector. We used a quartz capillary column (PE-5MS, 30 m × 0.25 mm) with a deposited stationary phase of copolymer (5% phenylmethylsilicone) 0.25 µm thick. The He carrier gas flow rate was 1 mL/min. The column temperature thermostat was programmed as follows: hold for 2 min at 75°C, heat to 100°C at 2°C/min, to 160°C at 4°C/min; and to 220°C at 2°C/min; hold at this temperature for 2 min. The duration of the final isothermal regime was 20 min at 230°C. Samples (0.2 µL) were injected with vaporizer temperature 180°C, detector 220°C, ionization potential 70 eV, and m/z 30-550.The contents of EO components were calculated using GC peak areas without correlation coefficients. Components were identified based on a comparison of retention times and full mass spectra with those of standard EO components and pure compounds and a search of the NBS, NIST, and Wiley mass spectrometric libraries.A total of 18 chemical components consisting of 99.98% of the EO were identified in seeds of Daucus carota sativa. According to the GC/MS results, the main components of carrot-seed EO were β-bisabolene (80.49%), α-asarone (8.8%), and cis-α-bergamoten (5.51%). The total amount of main components was 95.72% of the total EO content. Table 1 gives the chemical components and their molecular formulas and relative percent contents according to the mass spectrometric analyses.The main components of carrot-seed EO from France and Hungary were α-pinene (13%), β-pinene (18%), carotol (18%), and β-bisabolene [5,6]. However, the main components of EO from Uzbekistan were β-bisabolene (80.49%), asarone (8.8%), and cis-α-bergamoten (5.51%). The variation in the EO component compositions is probably due to growing conditions. The antiicrobial activity of the EO fractions against Candida albican and Staphylococcus aureus was determined by a modified Barry test method [7]. Table 2 gives the results. Table 2 shows that mixtures of terpenes and sesquiterpenes from carrot-seed EO exhibited a high antimicrobial activity and possibly protect seeds from bacterial and fungal infection. Pure α-asarone exhibited sedative and antipyretic properties; α-humulene, anticancer activity against MCF-7, PC-3, A-549, DLD-...

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A non-specific lipid-transfer peptide (nsLTP) with fungicidal activity was isolated from Daucus carota sativa carrot seeds. Peptides were purified by a method including aqueous extraction, anion-exchange chromatography over CM-TSK-650M, and HPLC over a column of 250/8/4 Protein@Peptide C 18 using an acetonitrile gradient. The molecular weight of the peptide was determined as 9624 Da by mass spectrometry. The peptide was found to have fungicidal activity against the pathogenic fungus Verticillium dahliae. The partial N-terminal sequence, which was highly homologous to the N-terminal sequences of lipid-transfer peptides from seeds of rice, tobacco, and maize, was determined using Edman automated sequencing.Key words: carrot seeds, fungicidal lipid-transfer peptides, N-terminal amino-acid sequence.Many fungicidal peptides from plant seeds have already been described. These include lipid-transfer peptides, main proteins of molecular weight 9-10 kDa that can bind and transfer various lipids through membranes [1]. We isolated and characterized previously two peptides from Daucus carota sativa (Apiaceae) carrot seeds that were similar to lipid-transfer peptides in molecular weight according to PAAG electrophoresis [2]. The goal of the present work was to isolate a homogeneous non-specific lipid-transfer peptide (nsLTP) from carrot seeds, determine the in vitro fungicidal activity against the pathogen Verticillium dahliae, and to identify its partial N-terminal sequence.The method for purifying cationic peptides from carrot seeds consisted of several steps. Proteins and peptides were extracted from seeds by phosphate buffer and precipitated from the extract by ammonium sulfate at 30-80% saturation. Highmolecular-weight proteins were removed by precipitation at 80°C with subsequent centrifugation. Table 1 gives the protein yields for the purification steps.The fraction of thermally stable peptides that was precipitated by ammonium sulfate at 80% saturation was then purified by anion-exchange chromatography over a column of Servacel DEAE 23SN. Then the peptide fraction that did not adsorb to the anion-exchange column was placed on a cation-exchange column with KM-TSK-650M. It was shown earlier that fungicidal proteins and peptides are adsorbed at low ionic strength onto strongly acidic SP-Toypearl cation-exchange resin or onto an affinity column with Affi-gel blue gel [3,4]. Then the peptide fraction bound to a column of KM-TSK-650M was eluted by a NaCl gradient to produce two fractions of cationic peptides AFP-1 (anti-fungal peptide 1) and AFP-2, which were collected, desalted by gel-chromatography over Molselect G-15, and used for further analysis.The molecular weights of the cationic peptides were determined by gel-electrophoresis in PAAG (15%) under dissociating conditions [5]. Figure 1 shows the results, from which it can be seen that the molecular weights of the peptides were 2.5-9 kDa. This agrees with the values for known antimicrobial peptides (AMP) [6][7][8].