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In this study, fruits, fruit flesh and seeds of Rosa damascena and Rosa canina were assayed for the composition of fatty acids, ascorbic acid, alpha-tocopherol, beta-carotene, and mineral elements. The concentration of linoleic acid in seed oil of R. damascena (54.18%) was higher than in R. canina (48.84%). Alpha-tocopherol concentrations were found to be 7.10 microg/g and 34.20 microg/g for R. damascena and R. canina fruits, respectively. Ascorbic acid conc. was determined as the highest in the fruit flesh (546 mg/100 g in R. damascena and 2,200 mg/100 g in R. canina), and as the lowest in the seeds of both species. R. damascena fruits were found to be richer in minerals such as Ca, Fe, K, Mn, Na, P, and Zn than R. canina fruits. The results of the present study showed that R. damascena fruits could be used as food and food additive equally as rose hip fruits.

The signaling pathways that allow plants to mount defenses against chewing insects are known to be complex. To investigate the role of jasmonate in wound signaling in Arabidopsis and to test whether parallel or redundant pathways exist for insect defense, we have studied a mutant (fad3-2fad7-2fad8) that is deficient in the jasmonate precursor linolenic acid. Mutant plants contained negligible levels of jasmonate and showed extremely high mortality (approximately 80%) from attack by larvae of a common saprophagous fungal gnat, Bradysia impatiens (Diptera: Sciaridae), even though neighboring wild-type plants were largely unaffected. Application of exogenous methyl jasmonate substantially protected the mutant plants and reduced mortality to approximately 12%. These experiments precisely define the role of jasmonate as being essential for the induction of biologically effective defense in this plant-insect interaction. The transcripts of three wound-responsive genes were shown not to he induced by wounding of mutant plants but the same transcripts could be induced by application of methyl jasmonate. By contrast, measurements of transcript levels for a gene encoding glutathione S-transferase demonstrated that wound induction of this gene is independent of jasmonate synthesis. These results indicate that the mutant will be a good genetic model for testing the practical effectiveness of candidate defense genes.

Walnuts of five cultivars (Sampion, Jupiter, Sejnovo, Elit, and Geisenheim 139) of Juglans regia were collected during the 2008 harvest in Cacak, Central Serbia. Two techniques of oil extraction were implemented - cold pressing and organic solvent extraction. The influence of the implemented methods on the fatty acid composition, tocopherol level as well as oxidative stability was examined. Predominant fatty acids were palmitic, oleic, linoleic, and linolenic acids. The oleic acid concentration ranged from 15.9_23.7% of the total fatty acids, while the linoleic acid concentration ranged from 57.2-65.1% and that of linolenic acid from 9.1-13.6%. The process of oil extraction had no significant effect on the concentration and composition of fatty acids in the oil. The total concentration of tocopherols ranged from 28.40 mg/100 g to 42.40 mg/100 g of the extracted oil. The most common tocopherol in all samples was gamma-tocopherol. The oil extracted using the Soxhlet method contained higher amounts of total tocopherols while the stability of the oil samples (expressed as induction period) ranged from 5.0 h to 7.1 hours. Reduced stability of the oil samples as measured by the Rancimat method was negatively correlated with the level of linolenic acid and total content of tocopherols.

The stability of olive and sunflower oils for domestic uses after frying cow steak or only heating were evaluated in the presence or absence of the carvacrol-rich essential oil of Thymbra capitata. The treatments consisted of sunflower and olive oils either enriched with 200 mg/l of T. capitata oil or without it, heating at 180 deg C for 20 min, or frying 100 g cow steak at the same temperature and for the same period of time. In all assays, acid, peroxide, and p-anisidine values were followed over time. The fatty acid profile was estimated before heating or frying as well as at the end of the experiment. The results showed that the type of fat as well as the type of treatment (frying or heating) was determinant for the acid, peroxide, and p-anisidine values found. The presence of the essential oil also demonstrated to affect those values depending on the type of the oil as well as on the type of the treatment (frying or heating). In contrast, the fatty acid profile did not change greatly.

Conventional beliefs surrounding the linolenic acid (LNA; cis-9 cis-12 cis-15 C18:3) biohydrogenation (BH) pathway propose that it converts to stearic acid (SA) without the formation of conjugated linoleic acid (CLA) as intermediate isomers. However, an advanced study (Lee and Jenkins, 2011) verified that LNA BH yields multiple CLAs. This study utilized the stable isotope tracer to investigate the BH intermediates of 13C-LNA with different pH conditions (5.5 and 6.5). The 13C enrichment was calculated as a 13C/12C ratio of labeled minus unlabeled. After 24 h, eight CLA isomers were significantly enriched on both pH treatment, this result verifies that these CLAs originated from 13C-LNA BH which supports the results of Lee and Jenkins (2011). The enrichment of cis-cis double bond CLAs (cis-9 cis-11 and cis-10 cis-12 CLA) were significantly higher at low pH conditions. Furthermore, the concentration of cis-10 cis-12 CLA at low pH was four times higher than at high pH conditions after a 3 h incubation. These differences support the LNA BH pathways partial switch under different pH conditions, with a strong influence on the cis-cis CLA at low pH. Several mono-, di-, and tri-enoic fatty acid isomers were enriched during 24 h of incubation, but the enrichment was decreased or restricted at low pH treatment. Based on these results, it is proposed that low pH conditions may cause a changed or limited capacity of the isomerization and reduction steps in BH.

The activation of plant defensive genes in leaves of tomato plants in response to herbivore damage or mechanical wounding is mediated by a mobile 18-amino acid polypeptide signal called systemin. Systemin is derived from a larger, 200-amino acid precursor called prosystemin, similar to polypeptide hormones and soluble growth factors in animals. Systemin activates a lipid-based signaling cascade, also analogous to signaling systems found in animals. In plants, linolenic acid is released from membranes and is converted to the oxylipins phytodienoic acid and jasmonic acid through the octadecanoid pathway. Plant oxylipins are structural analogs of animal prostaglandins which are derived from arachidonic acid in response to various signals, including polypeptide factors. Constitutive overexpression of the prosystemin gene in transgenic tomato plants resulted in the overproduction of prosystemin and the abnormal release of systemin, conferring a constitutive overproduction of several systemic wound-response proteins (SWRPs). The data indicate that systemin is a master signal for defense against attacking herbivores. The same defensive proteins induced by wounding are synthesized in response to oligosaccharide elicitors that are generated in leaf cells in response to pathogen attacks. Inhibitors of the octadecanoid pathway, and a mutation that interrupts this pathway, block the induction of SWRPs by wounding, systemin, and oligosaccharide elicitors, indicating that the octadecanoid pathway is essential for the activation of defense genes by all of these signals. The tomato mutant line that is functionally deficient in the octadecanoid pathway is highly susceptible to attacks by Manduca sexta larvae. The similarities between the defense signaling pathway in tomato leaves and those of the defense signaling pathways of macrophages and mast cells of animals suggests that both the plant and animal pathways may have evolved from a common ancestral origin.

The compositions and concentrations of lipid classes, fatty acids and tocopherols were determined in the lipids from Spirulina platensis. Total lipids (TL) recovered using chloroform : methanol (2:1, v/v) were found to be 163.5 g/kg (on dry weight basis). The level of neutral lipids was the highest, followed by glycolipids and phospholipids, respectively. Among TL and lipid classes, palmitic, gamma-linolenic and linoleic acids were the dominating fatty acids. Compared with the neutral lipids, the polar fractions were generally characterised by higher percentages of saturated fatty acids. The recovered lipids were characterised by high percentage of tocopherols, wherein alpha-tocopherol constituted about 73% of total tocopherols present, the rest having been gamma-tocopherol. Spirulina platensis lipids exhibited a strong radical scavenging activity towards stable DPPH free radicals, whereas 27% of DPPH radicals were quenched after 2 h incubation. TL and lipid classes inhibited the growth of different microorganisms except gram-negative bacteria. At high concentrations, the tested lipids appeared more effective against A. niger (28.3+/-1.53 mm).

The urea complexation was used to concentrate n-3 fatty acids (FA) from crude and refined commercial salmon oils. The experimental procedure included salmon oil saponification, free fatty acid (FFA) collection, formation of urea-FFA inclusion complexes, extraction of free n-3 FA and further analysis by gas-liquid chromatography of the corresponding FA methyl esters. Differences between crude and refined salmon oil could be observed. Crude oil provided higher typical odour, viscosity and suspension particle values, whereas crude salmon oil showed higher FFA and impurities content while p-anisidine and iodine values, moisture content and formation of conjugated dienes and trienes did not provide any significant differences between both oils; refined oil showed lower a* and b* scores when compared to its counterpart crude oil. Related to the n-3 PUFA concentration, a decrease in saturated fatty acids C 14:0, C 16:0, and C 18:0 and monounsaturated fatty acids C 18:1 9c, and C 18:1 11c, as well as a high yield of n-3 PUFA, EPA+DHA and total PUFA recovering could be observed starting from both crude and refined oils, which confirmed salmon oil to be a profitable source of such highly valuable constituents. Factors such as reaction temperature and ureaFFA ratio showed to be markedly significant to achieve higher value concentrations.

A variety of agricultural plant species, including corn, respond to insect herbivore damage by releasing large quantities of volatile compounds and, as a result, become highly attractive to parasitic wasps that attack the herbivores. An elicitor of plant volatiles, N-(17-hydroxylinolenoyl)-L- glutamine, named volicitin and isolated from beet armyworm caterpillars, is a key component in plant recognition of damage from insect herbivory. Chemical analysis of the oral secretion from beet armyworms that have fed on 13C-labeled corn seedlings established that the fatty acid portion of volicitin is plant derived whereas the 17-hydroxylation reaction and the conjugation with glutamine are carried out by the caterpillar by using glutamine of insect origin. Ironically, these insect-catalyzed chemical modifications to linolenic acid are critical for the biological activity that triggers the release of plant volatiles, which in turn attract natural enemies of the caterpillar