The dynamics of the fatty acid (FA) composition of total lipids in needles of Siberian spruce (Picea obovata L.) during the first half (March–July) of the 2010 vegetation season has been studied. Three maxima of the unsaturated fatty acid (UFA) content with increased levels of α-linolenic acid are revealed in the postwinter (March 10–April 6), spring (April 20–May 18), and summer (June 1–July 20) periods. During postwinter and spring vegetation, the UFA increase is accompanied by an increase in the oleic and linoleic desaturation ratios. The spring peak of the 18:3ω3 content coincides with the spring peak in chlorophylls in the light-harvesting complexes of photosynthetic units and with the onset of the net CO2 assimilation. The summer peak is characterized by the level of chlorophylls, which is the highest over the entire monitoring period. The possible ways that the FA is involved in the rearrangement of the structural and functional organization of the photosynthetic apparatus of a coniferous plant are discussed.

A comparative analysis of the fatty acid (FA) composition of lipids in the calluses and needles of Scots pine (Pinus sylvestris), white spruce ( Picea pungens ), Korean pine ( Pinus koraiensis ), and Siberian larch ( Larix sibirica ) has been carried out using the method of gas-liquid chromatography–mass spectrometry. In all cases, the total content of monounsaturated FA in the lipids of callus was higher than in the lipids of needles. Oleic acid (C18:1) represented a significant part of the composition of these acids. It was established that the lipids of callus of the studied species are characterized by a lower relative content and a smaller variety of Δ5-acids than the lipids of needles of the same species. It was shown that species-specificity of FA composition of the lipids of needles remains the same in the plant tissues grown in culture in vitro and does not depend on the material used to initiate the callus. Qualitative differences in the FA composition of the callus in culture and the needles of whole plant were detected. It was shown that the embryogenetic ability of the callus is associated with high content of oleic acid.

Fatty acid (FA) composition of total lipids in embryogenic and nonembryogenic calli of Siberian larch (Larix sibirica Ledeb.) was investigated by the method of GC-MS. We detected a high content of oleic acid in total lipids of embryogenic cell culture (32–56% by weight of total FA), which apparently depends on a high activity of acyl carrier protein (stearoyl-ACP-Δ9-desat-urase). At the same time, activity of Δ12-desaturase in the cells of embryogenic calli was considerably (2–3 times) lower than in nonembryogenic calli. We discuss a possibility that concentration of FA (oleic and linoleic acids) may be used as a marker of embryogenic potential when promising cell lines of Siberian larch are screened in the stage of early embryogenesis.

Методом газожидкостной хроматографии изучен жирнокислотный состав липидов каллусов лиственницы Гмелина (L. gmelinii) и лиственницы сибирской (L. sibirica). Жирнокислотный состав липидов каллусов характеризовался высоким содержанием ненасыщенных жирных кислот, составляющих для L. gmelinii 57,7% и для L. sibirica 59,9%, среди которых линолевая и олеиновая составляла 24,5 и 11,2% для L. gmelinii. и 26,6 и 14,8% для L. sibirica соответственно В составе липидов каллусов L.gmtlinii содержание ∆5-UPIFA составляло 12,3%, для L. Sibirica – 11,2%. В составе ∆5-UPIFA липидов каллусов лиственницы обоих видов содержание пиноленовой кислоты (∆5,9,12–18:3) составляло 6%. Содержание длинноцепочных насыщенных С20:0, С22:0, С23:0, С24:0 кислот составляло для каллусов L. gmelinii 11,4%, для L. sibirica – 9,1%.

The fatty acid (FA) composition of common pine (Pinus sylvestris L.) needle lipids was studied. It was shown that FA composition of needle lipids changed during the entire growth period (from March to October) under the influence of environmental factors (temperature, solar radiation) affecting the biosynthesis of chloroplast membrane lipids in pine needles. Among needle lipid FAs, unsaturated polymethylene-interrupted FAs (Δ5-UPIFA) were identified: pinolenic, skiadonic, coniferonic, and other); in March and April, their content attained 16.1 and 16.9% of total FAs; it decreased in June to 6.0% and increased again in September to 20.4%.

The study was focused on fatty acid (FA) composition of lipids from the seedlings and roots of crops having different cold resistance and grown at 27°C or 4°C. Biosynthesis of FA in the lipids of seedlings and roots of cold-susceptible maize ( Zea mays L.) at both growth temperatures was controlled by chloroplast ω6 desaturase and microsomal ω6 desaturase, respectively. The content of linoleic acid was 56.2% and 43.3% in the coleoptiles of maize seedlings grown at 4 and 27°C, respectively, and in the roots it was 52.2% and 38.5%, respectively. The content of α-linolenoic acid in the coleoptiles was 6.7–6.8% at both temperatures, while in the root lipids it was higher at low temperature (3.15% at 27°C vs. 4.7% at 4°C). FA biosynthesis in the seedling coleoptiles of wheat ( Triticum aestivum L.) and Siberian wild rye ( Elymus sibiricus L.) grown at low temperature was controlled by the chloroplast ω3 desaturase. A minor increase in the content of α-linolenoic acid was observed at low temperature: 29.7% to 30.2% in wheat and 22.8% to 25.8% in wild rye. In the root tissues of these species, the biosynthesis of α-linolenoic acid was controlled by the microsomal ω3 desaturase. The content of α-linolenoic acid was higher at low temperature: in wheat it was 6.1% at 27°C and 17.1%, and 4°C, while in Siberian wild rye, 7.1% and 12.0% at 4 and 27°C, respectively.

The study was focused on fatty acid (FA) composition of lipids from seedlings and roots of crops having different cold resistance and grown at 27 degrees C and 4 degrees C. FA biosynthesis in the lipids of seedlings of cold-susceptible maize (Zea mays L.) under both growth temperatures was controlled by chloroplast omega-6 desaturase and in the lipids of roots, by microsomal omega-6 desaturase. The content of linoleic acid in coleoptiles of maize seedlings grown at 4 and 27 degrees C was 56.2% and 43.3%, respectively, and in the roots, it was 52.2% and 38.5%, respectively. The content of alpha-linolenoic acid in coleoptiles was 6.7-6.8% at both temperatures and in root lipids it was higher at low temperature (3.15% at 27 degrees C vs. 4.7% at 4 degrees C). Biosynthesis of FA in seedling coleoptiles of wheat (Triticum aestivum L.) and Siberian wildrye (Elymus sibiricus L.) grown at low temperature was controlled by chloroplast omega-3 desaturase. A small increase of the alpha-linolenoic acid content was observed at low temperature: from 29.7% to 30.2% in wheat and from 22.8% to 25.8% in wildrye. In root tissues of these species biosynthesis of alpha-linolenoic acid was controlled by microsomal omega-3 desaturase. The content of alpha-linolenoic acid increased at low temperature: from 6.1% to 17.1% in wheat and from 7.1% to 12.0% in Siberian wildrye at 27 and 4 degrees C, respectively.

Изучен жирнокислотный состав липидов проростков и корней злаков контрастных по холодоустойчивости растений при двух температурах роста: 27 и 4°С. Биосинтез жирных кислот (ЖК) в липидах проростков холодочувствительного злака кукурузы (Zea mays L.) при обеих температурах контролировался хлоропластной 6-десатуразой, а в липидах корней – микросомальной 6-десатуразой. При низкой температуре содержание линолевой кислоты в колеоптилях проростков кукурузы составляло 56.2 против 43.3% в контроле и 52.2 против 38.5% – в корнях. Содержание -линоленовой кислоты при этом составляло 6.7–6.8% и увеличивалось в липидах корней с 3.1 до 4.7%. Биосинтез ЖК липидов в колеоптилях проростков пшеницы (Triticum aestivum L.) и пырейника сибирского (Elymus sibiricus L.) при низкой температуре контролировался хлоропластной 3-десатуразой, которая вызывала небольшое увеличение содержания -линоленовой кислоты – с 29.7 до 30.2% в пшенице и с 22.8 до 25.8% в пырейнике. В тканях корней этих злаков биосинтез -линоленовой кислоты контролировался микросомальной 3-десатуразой: содержание -линоленовой кислоты увеличивалось с 6.1 до 17.1% в пшенице и с 7.1 до 12.0% в пырейнике сибирском.

The fatty acid (FA) composition of callus lipids in two pine species, Pinus sibirica Du Tour and P. sylvestris L. was studied. Callus lipids were characterized by a high content of unsaturated FAs: 81.7% in P. sibirica and 63.2% in P. sylvestris. Among them, oleic and linoleic acids predominated (22.9 and 34.0% of total FAs in P. sibirica and 17.6 and 27.8% in P. sylvestris, respectively). Callus lipids also contained Δ5-UPIFA (unsaturated polymethyle-interrupted FAs), where pinoleic and sciadonic acids predominated. A comparison of FAs in the lipids of P. sylvestris calluses derived from needle and needle photosynthesizing tissues of this pine species showed that callus lipids were characterized by a greater diversity of Δ5-UPIFA but a lower degree of FA unsaturation and he higher level of Δ5-UPIFA.

Методом ГЖХ изучен жирнокислотный состав запасных липидов эндосперма и зародыша семян двух видов сосны Pinus sibirica и P. sylvestris и возможные пути биосинтеза этих кислот. Жирнокислотный состав липидов зародыша и эндосперма в семенах P. sibirica характеризуется более высоким содержанием олеиновой кислоты (соответственно 22.0 и 24.0%), чем в таких же липидах P. sylvestris (18.7 и 14.0%), тогда как линолевая кислота преобладала в липидах зародыша и эндосперма у P. sylvestris (44.8 и 46.8%) и у P. sibirica (43.5 и 42.6%), что, вероятно, обусловлено высокой экспрессией гена стеароил- ацил-липидной десатуразы и гена fad2 микросомальной 6-ацил-липидной десатуразы. В составе запасных липидов семян хвойных присутствуют -ненасыщенные ЖК ( -НПМР): таксолеиновая (С18 : 2 5,9), эфедриновая (С18 : 2 5,11), пиноленовая (С18 : 3 5,9.12), скиадоновая (С18 : 3 5,11.14), конифероновая (С18 : 4 5,9,12.15). В составе -НПМР липидов эндосперма и зародыша семян P. sylvestris содержание пиноленовой кислоты было выше (22.1 и 19.6%), чем в семенах P. sibirica (19.1 и 18.6%).

The fatty acid (FA) composition of storage lipids in the seed endosperms and embryos of two pine species, Pinus sibirica and P. sylvestris, and possible biosynthetic pathways of these acids were studied by the GLC method. Linoleic acid predominated in the embryo and endosperm lipids of both P. sibirica (43.5 and 42.6%) and P. sylvestris (44.8 and 46.8%); this was evidently determined by a high expression of the gene encoding stearoyl-Δ9 acyl-lipid desaturase and the fad2 gene encoding microsomal ω6 acyl-lipid desaturase. P. sibirica lipids of the embryo and endosperm contained more oleic acid (22.0 and 24.0%, respectively) than corresponding P. sylvestris lipids (18.7 and 14%). Storage lipids of conifer seeds contain Δ5-unsaturated FAs: taxoleic (18:2Δ5,9), ephedrenic (18:2Δ5,11), pinoleenic (18:3Δ5,9,12), skiadonic (18:3Δ5,11, 14), and coniferonic (18:4Δ5,9,12,15). In the endosperm and embryos of P. sylvestris, the content of pinolenic acid was higher (22.1 and 19.6%) than in P. sibirica seeds (19.1 and 18.6%).

Fatty acid (FA) composition of vacuolar membrane lipids from storage tissues of umbelliferous plants, viz., parsnip ( Pastinaca sativa L.), parsley ( Petroselinium crispum L.), and carrot ( Daucus carota L.) is studied by gas-liquid chromatography and the FA biosynthetic pathways are considered. Vacuolar membrane lipids are characterized by high (78% of the total FA pool) content of unsaturated FA among which linoleic acid is predominant. Its content in vacuolar lipids of parsnip, parsley and carrot is 53.5, 55.1, and 54.9%, respectively. Parsnip and parsley vacuolar lipids contain large amounts of hexadecadienoic C16:2ω6 acid (8.0 and 4.6%, respectively). The content of α-linolenic acid in vacuolar lipids of tested plants varies from 4.8 to 7.3%. Palmitic acid (18.0–20.7%) predominates among saturated FA. High content of linoleic and hexadecadienoic acid in parsnip and parsley vacuolar lipids is suggestive of a crucial role of the microsomal ω6 fatty-acid desaturase fad2 gene in resistance and acclimation of plants to low temperatures.

The fatty acid (FA) composition of vacuolar membrane lipids from the storage tissues of parsnip ( Pastinaca sativa L.), parsley ( Petroselinum crispum L.), and carrot ( Daucus carota L.) was studied by gasliquid chromatography, and possible pathways of the biosynthesis of these acids are considered. A high level of unsaturated FAs (up to 78% of the total FA amount) was characteristic of these membrane lipids with the predominance of linoleic acid, which content in vacuolar lipids of parsnip, parsley, and carrot was 53.5, 55.1, and 54.4%, respectively. A high content of hexadienoic acid (C16:2ω6) was characteristic of the vacuolar lipids of parsnip and parsley (8.0 and 4.6%. respectively); the content of α-linolenic acid in the vacuolar lipids of these plants was 4.4–7.3%. Palmitic acid predominated among the saturated FAs (18.0–20.4%).

Fatty acid composition of lipids, extracted from callus cultures derived from meristem tissue of larch (Larix gmelinii (Rupr.) Rupr.) was studied by means of gas-liquid chromatography and compared with the fatty acid composition of cellular membranes from larch seeds and needles. In cultured calli, linoleic and alpha-linolenic acids were predominant polyunsaturated fatty acids (22 and 10%, resp.). In microsomal membranes of seeds, most abundant polyunsaturated fatty acids were linoleic and pinolenic acids (43 and 29%), while in needle chloroplast membranes, it was alpha-linolenic acid (40%). We suggest that these differences may be due to the expression of fad2 and fad3 genes in callus cells, jad2 and Delta 5-acyl-lipid desaturase genes in seed cells, and fad7 and fad8 genes in needle cells.