Lipids of the Green Alga BotryococcusCultured in a Batch Mode

The lipid fraction of the green alga Botryococcuscultured in a batch mode was found to contain polar lipids (more than 50% of the total lipids), di- and triacylglycerols, sterols and their esters, free fatty acids, and hydrocarbons. In aging culture, the content of polar lipids somewhat decreased and that of triacylglycerols increased by more than four times. The content of hydrocarbons in the algal biomass did not exceed 0.9% and depended little on the culture age. Intracellular lipids contained saturated and unsaturated (mono-, di-, and trienoic) fatty acids. The maximum content of C_{16 : 3}and -C_{18 : 3}fatty acids (up to 35% of the total fatty acids) was detected in the phase of active growth. The extracellular and intracellular lipids of the alga differed in the proportion of particular lipids and in the fatty acid pattern.     

The effect of temperature on the lipid composition of Botryococcus

The lipid composition of the green alga Botryococcus was studied at three different cultivation temperatures: suboptimal, optimal, and supraoptimal. Cultivation at the supraoptimal temperature was found to considerably inhibit the synthesis of nearly all intracellular lipids, except for triacylglycerides, and to influence their fatty acid composition. In particular, the content of trienoic fatty acids was significantly lower at the supraoptimal than at the optimal cultivation temperature. At the same time, the fatty acid composition of the extracellular lipids of the alga virtually did not depend on cultivation temperature.     

The Effect of Temperature on the Lipid Composition of the Green Alga Botryococcus

The lipid composition of the green alga Botryococcus was studied at three different cultivation temperatures: suboptimal (18°C), optimal (25°C), and supraoptimal (32°C). Cultivation at the supraoptimal temperature was found to considerably inhibit the synthesis of nearly all intracellular lipids, except for triacylglycerides, and to influence their fatty acid composition. In particular, the content of trienoic fatty acids was significantly lower at the supraoptimal than at the optimal cultivation temperature. At the same time, the fatty acid composition of the extracellular lipids of the alga virtually did not depend on cultivation temperature.     

Lipid analysis of Greek walnut oil (Juglans regia L.)

The walnut oil (Juglans regia L.) total lipids (TL) were extracted by the Bligh-Dyer method and the lipid classes have been isolated by chromatographic techniques and they were analyzed by high performance thin layer chromatography (HPTLC)/FID and GC-MS. The oil was found to be rich in neutral lipids (96.9% of total lipids) and low in polar lipids (3.1% of total lipids). The neutral lipid fraction consisted mainly of triacylglycerides whereas the polar lipids mainly consisted of sphingolipids. GC-MS data showed that the main fatty acid was linoleic acid. Unsaturated fatty acids were found as high as 85%, while the percentage of the saturated fatty acids was found 15%. Two types of liposomes were prepared from the isolated walnut oil phospholipids and characterized as new formulations. These formulations may have future applications for encapsulation and delivery of drugs and cosmetic active ingredients.     

Influence of nitrogen deficiency on biochemical composition of the green alga <Emphasis Type="Italic">Botryococcus</Emphasis>

A study has been carried out to investigate the influence of nitrogen deficiency on intracellular lipid composition, including total fatty acid composition of lipids, polar lipids, and triacylglycerols, of the alga Botryococcus braunii Kütz IPPAS H-252 in batch culture. Under nitrogen limitation, the alga accumulates lipids as triacylglycerols and the total fatty acid (FA) composition changes: trienoic acids decrease (from 52.8–57.2 to 19.5–24.7% of the total FAs) and the oleic acid increases (from 1.1–1.2 to 17.1–24.4%) as does the saturated acids (from 23.7–26 to 32.9–46.1%). A similar rearrangement in the FA spectrum occurs at later times in the control culture, but it is less pronounced. Under nitrogen limitation, considerable changes in the polar lipid FAs are registered at day 13: saturated acids increase (from 28.6–35.5 to 76.8%) and all polyenoic acids markedly decrease (from 56.9–64.1 to 6.8%). Changes in the triacylglycerol fatty acid spectrum are seen on day 7: the oleic acid increases (from 14.7 to 34.2%) and remains at a high level till the end of the culture. In the control, triacylglycerols with large contents of oleic acid are detected at day 13, the total lipids and triacylglycerols still remaining unchanged.     

Characteristics of lipid composition in arthrospores, budding cells and mycelium of the fungus Mucor hiemalis

The fungus Mucor hiemalis F-1156, which is believed to be monomorphic, was found to be able to grow dimorphically in a liquid medium that is free of chemical agents influencing morphogenesis. The growing mycelium produced arthrospores in large amounts. The lipids of the mycelium, yeastlike budding cells, and arthrospores differed in the contents of saturated and unsaturated fatty acids and in the proportion of polar and neutral lipids. The arthrospores contained more monoenoic fatty acids in the total lipids, more triacylglycerides and sterol esters in the neutral lipids, and more phosphatidylcholine and phosphatidylethanolamine in the polar lipids than the yeastlike cells. These differences in the lipid composition of different types of fungal cells should be taken into account in the studies of the lipogenesis of M. hiemalis.     

Composition of lipids from yeast-like and mycelial cells of the fungus Mucor hiemalis, grown in the presence of 4-chloroaniline

The fungus Mucor hiemalis, which is commonly thought to be monomorphic, produced two types of cells, yeastlike and mycelial, during growth in a medium containing 4-chloroaniline. Among the polar lipids of yeastlike cells, diphosphatidylglycerol was dominant, while phosphatidylcholine and phosphatidylethanolamine were present in minor amounts. Conversely, mycelial cells mainly contained phosphatidylcholine and phosphatidylethanolamine, whereas the content of diphosphatidylglycerol was low. The neutral lipids of yeastlike cells were dominated by diacylglycerides, sterols, and fatty acids. The content of triacylglycerides and sterol esters was low. Yeastlike cells contained higher amounts of saturated fatty acids and lower amounts of unsaturated fatty acids than the mycelium. The content of stearic acid in the fatty acids of the mycelium grown in the presence of 4-chloroaniline was as high as 25.3-29.9%.     

Lipid Composition of the Arthrospores, Yeastlike Cells, and Mycelium of the Fungus Mucor hiemalis

The fungus Mucor hiemalisF-1156, which is believed to be monomorphic, was found to be able to grow dimorphically in a liquid medium that is free of chemical agents influencing morphogenesis. The growing mycelium produced arthrospores in large amounts. The lipids of the mycelium, yeastlike budding cells, and arthrospores differed in the contents of saturated and unsaturated fatty acids and in the proportion of polar and neutral lipids. The arthrospores contained more monoenoic fatty acids in the total lipids, more triacylglycerides and sterol esters in the neutral lipids, and more phosphatidylcholine and phosphatidylethanolamine in the polar lipids than the yeastlike cells. These differences in the lipid composition of different types of fungal cells should be taken into account in the studies of the lipogenesis of M. hiemalis.     

Lipid Composition of the Yeastlike and Mycelial Mucor hiemalis Cells Grown in the Presence of 4-Chloroaniline

The fungus Mucor hiemalis F-1156, which is commonly thought to be monomorphic, produced two types of cells, yeastlike and mycelial, during growth in a medium containing 4-chloroaniline. Among the polar lipids of yeastlike cells, diphosphatidylglycerol was dominant, while phosphatidylcholine and phosphatidylethanolamine were present in minor amounts. Conversely, mycelial cells mainly contained phosphatidylcholine and phosphatidylethanolamine, whereas the content of diphosphatidylglycerol was low. The neutral lipids of yeastlike cells were dominated by diacylglycerides, sterols, and fatty acids. The content of triacylglycerides and sterol esters was low. Yeastlike cells contained higher amounts of saturated fatty acids and lower amounts of unsaturated fatty acids than the mycelium. The content of stearic acid in the fatty acids of the mycelium grown in the presence of 4-chloroaniline was as high as 25.3–29.9%.     

Membrane Lipids of Mycoplasma hominis

Essentially all of the lipids of Mycoplasma hominis (200 mug/mg of cell protein) were found to be located in the cell membrane. Over one-half were neutral lipids incorporated from the growth medium and consisting of 43% free cholesterol, 19% esterified cholesterol, 23% triglycerides, 10% free fatty acids, and small amounts of di- and monoglycerides. The polar lipids accounting for about 40% of the total were synthesized by the organisms. Phosphatidylglycerol was the predominant lipid of this fraction. The minor components, tentatively identified as lysophosphatidylglycerol and phosphatidic acid, seem to represent breakdown products of phosphatidylglycerol. No glycolipids were detected. Being unable to synthesize long-chain fatty acids, M. hominis utilized the fatty acids of the growth medium for polar lipid synthesis, preferentially the saturated ones, so that the polar lipids had highly saturated hydrocarbon chains. It is proposed that the large take up of unsaturated neutral lipids and cholesterol from the medium offsets the marked condensing effect of the saturated polar lipids, although electron paramagnetic resonance spectrometry of spin-labeled fatty acids incorporated into the M. hominis membrane indicated that the lipid region is still more rigid than that of the Acholeplasma laidlawii membrane.     

Effect of Nitrogen Limitation on the Growth and Lipid Composition of the Green Alga <Emphasis Type="Italic">Botryococcus braunii</Emphasis> Kutz IPPAS H-252

The effect of nitrogen limitation in a medium on the composition of intracellular lipids in the alga Botryococcus braunii Kutz IPPAS H-252 in the course of culture development was investigated. Under the conditions of nitrogen limitation, the alga under investigation accumulated lipids as triacylglycerols, and this process was accompanied by substantial changes in the total fatty acid (FA) composition, which were manifested in a decrease in trienoic acids (from 52.8–57.2 to 19.5–24.7% of total FAs) and an increase in the content of oleic (from 1.1–1.2 to 17.1–24.4%) and saturated (from 23.7–26.0 to 32.9–46.1%) acids. In the control culture, the directionality of FA redistribution was less marked, and these changes were noticed at the later stages of culture development. Under nitrogen limitation, marked changes in the FA composition of polar lipids occurred by the 13th day, and they were characterized by an increase in the content of saturated acids (up to 76.8%) and a dramatic decrease in the content of all polyenoic acids (up to 6.8%). The changes in the FA composition of triacylglycerols were noticed as early as by the 7th day; these changes consisted in an increase in the content of oleic acid, and its high content (28.4–38.4%) was maintained up to the end of culturing. In the control culture, triacylglycerols with a high content of oleic acid were found by the 13th day, although, by this time, the content of total lipids and triacylglycerols did not change.__________Translated from Fiziologiya Rastenii, Vol. 52, No. 3, 2005, pp. 357–365.Original Russian Text Copyright © 2005 by Zhila, Kalacheva, Volova.     

Liposomal formulations from phospholipids of Greek almond oil. Properties and biological activity

The seeds of the almond tree [(Prunus dulcis (Mill.) D. A. Webb. (syn. Prunus amygdalus)] were collected in two different periods of maturity and were studied for their lipid content. The total lipids (TL) were extracted by the Bligh-Dyer method and the lipid classes have been isolated by chromatographic techniques and were analyzed by HPTLC coupled with a flame ionization detector (HPTLC/FID) and GC-MS. The oils were found to be rich in neutral lipids (89.9% and 96.3% of total lipids) and low in polar lipids (10.1% and 3.7% of total lipids) for the immature and mature seed oils, respectively. The neutral lipid fraction consisted mainly of triacylglycerides whereas the polar lipids mainly consisted of phospholipids. GC-MS data showed that the main fatty acid for both oils was 9-octadecenoic acid (oleic acid). The unsaturated fatty acids were found as high as 89.4% and 89.7%, while the percentage of the saturated fatty acids was found 10.6% and 10.3% for the immature and mature seed oils, respectively. Liposomes were prepared from the isolated phospholipids using the thin lipid film methodology, and their physical properties were characterized. Cytotoxicity was found absent when assayed against normal and cancerous cell lines. These new formulations may have future applications for encapsulation and delivery of drugs and cosmetically active ingredients.     

Seasonal dynamics of fatty acid composition in female northern pike (Esox lucius L.)

Seasonal changes in the fatty acid composition of neutral and polar lipids were measured in the ovary, liver, white muscle, and adipopancreatic tissue of northern pike. The role of environmental and physiological factors underlying these changes was evaluated. From late summer (August–September) to winter (January–March), the weight percentage of n-3 polyunsaturated fatty acids (especially 22:6n3) declined significantly in the neutral lipids of all somatic tissues examined. However, large quantities of n-3 polyunsaturated fatty acids accumulated in the recrude cing ovaries during fall and the weight percentage of n-3 polyunsaturated fatty acids in ovary polar lipids also increased significantly. Additionally, the n-3 polyunsaturated fatty acid content of somatic polar lipids increased significantly during fall due to increases in the total polar lipid content of the somatic tissues. This suggests that during fall n-3 polyunsaturated fatty acid are diverted away from somatic neutral lipids and thereby conserved for use in ovary construction and for incorporation into tissue polar lipids. The percentage of n-3 polyunsaturated fatty acid in ovary neutral lipids also declined during fall and early winter, perhaps as an adaptation to conserve these fatty acids for storage in oocyte polar lipids and later incorporation into cellular membranes of the developing embryo. Reductions in the n-3 polyunsaturated fatty acids content of somatic and ovarian neutral lipids during fall were compensated for specifically by increases in the percentage of monounsaturated fatty acids rather than saturated fatty acids. This suggests that the ratio of saturated to unsaturated fatty acids in pike neutral lipid, is regulated physiologically, and hence may influence the physiological functioning of these lipids. During fall and early winter the percentage of saturated fatty acids declined significantly in the polar lipids of all tissues examined. This change was consistent with the known effects of cold acclimation on the fatty acid composition of cellular membranes. As the ovaries were recrudescing from September to January, liver polar lipids exhibited significant decreases in the percentage of total polyunsaturated fatty acids and n-3 polyunsaturated fatty acids and increases in monounsaturated fatty acids, and acquired a fatty acid composition very similar to that of ovary polar lipids. Therefore, seasonal changes in the percentage of polyunsaturated and monounsaturated fatty acids in liver polar lipids probably reflect the liver's role in vitellogenesis rather than the effects of temperature on membrane fatty acid composition. At all times of year, the fatty acid compositions of white muscle and adipopancreatic tissue neutral lipids were very similar, which may indicate a close metabolic relationship between these lipid compartments.Abbreviations AP adipopancreatic - BHT butylated hydroxytoluene - CI confidence interval - EFA essential fatty acids - MUFA monounsaturated fatty acids - NL neutral lipids - PL polar lipids - PUFA polyunsaturated fatty acids - SFA saturated fatty acids     

Effect of salinity on the biochemical composition of the alga <Emphasis Type="Italic">Botryococcus braunii</Emphasis> Kütz IPPAS H-252

The effect of 0.3 and 0.7 M NaCl on biomass yield, total nitrogen content, intracellular lipid content, and fatty acid profile of the lipids of the alga Botryococcus braunii IPPAS H-252 in different phases of the culture cycle was studied. The presence of sodium chloride in the medium inhibited the growth of algal cells for the first 3 days of the experiment, causing a decrease in total nitrogen, enhanced synthesis of triacylglycerols, and considerable changes in the lipid fatty acid profile: decreases in polyenoic acid contents (from 68.34% to 29.38% and 12.8%) and proportions of long-chain saturated acids (from 0.53% to 5.3% and 14.13% of the total fatty acids) at 0.3 M NaCl and 0.7 M NaCl, respectively. In later phases of the culture, at 0.3 M NaCl, the content of polyenoic acids rose to the values characteristic of the active growth phase of this alga. At 0.7 M NaCl, the proportion of polyenoic acids grew less significantly, but biomass concentration and total nitrogen increased, similarly to the experiment with 0.3 M NaCl.     

Specificity of Lipid Composition in Two Botryococcus Strains,the Producers of Liquid Hydrocarbons

The structure of liquid hydrocarbons and fatty acids produced by the green alga Botryococcus was identified. Two representatives of this alga, Botryococcus braunii Kütz, strain IPPAS H-252, introduced into culture earlier and an organism isolated for the first time from the Shira Lake, were used for this identification. Fatty acid composition of B. braunii, strain H-252, lipids was characterized by a high content of trienoic acids of C16–C18 series. The hydrocarbon composition of this strain was represented by straight-chain and branched-chain C14–C28 components; long-chain linear aliphatic C20–C27 hydrocarbons (54.4%) and 2,6,10,14-tetramethylhexadecane (20.5%) predominated among them. The strain H-252 differed in its fatty acid and hydrocarbon composition from the strains described earlier as Botryococcus braunii. The fatty acid composition of the Botryococcus isolate was represented mainly by C12–C32 saturated and monoenoic acids. The hydrocarbons formed by this isolate were represented by dienoic and trienoic components. C29 (48.9–56.3%) and C31 (11.1–16.3%) hydrocarbons predominated among the C23–C31 dienoic hydrocarbons, and C27, C29, and C31 trienoic hydrocarbons comprised 2.5–2.6% of total hydrocarbons. This type of hydrocarbons and the lipid fatty acid composition were characteristic for the race A of B. braunii.     

Metabolic characteristics and lipid composition of yeastlike cells and mycelium of Mucor circinelloides var. lusitanicus INMI grown at a high glucose content in the medium

It is shown that the fungus Mucor circinelloides var. lusitanicus INMI grown under aerobic conditions in a medium with a high glucose concentration (20%) is capable of both yeastlike and mycelial growth. In the mycelium, the activity of NAD-dependent isocitrate dehydrogenase was more than twice as high as in yeastlike cells, whereas the isocitrate lyase activity was lower. A number of significant differences were found in the lipid composition of the cells of two different morphological variants. Yeastlike cells contained more polar lipids and free fatty acids and less principal reserve lipids (triacylglycerides) than mycelial cells; the content of gamma-linolenic acid and the degree of lipid unsaturation were significantly lower in these cells than in the mycelium. In yeastlike cells, glycolipids composed the bulk of polar lipids; the proportion of phospholipids (primarily phosphatidylserine, phosphatidylcholine, phosphatidylethanolamine, and cardiolipin) was lower. The relationship between cellular metabolism and the lipid composition of fungal cells of different morphotypes grown at high concentrations of glucose, one of the main inducers of dimorphic growth, is discussed.     

Lipids in fruiting bodies of the basidiomyceteOudemansiella mucida

Dried fruiting bodies of the basidiomyceteOudemansiella mucida contain 29.1% total lipids. Their qualitative analysis revealed the presence of mono-, di-, triglycerides, sterols, free fatty acids and sterolesters. Quantitatively most significant were triglycerides (37.9%) and free fatty acids (29.7%). The phospholipid fraction contained phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and phosphatidic acid. Gas chromatography showed the presence of a broad spectrum of fatty acids. The ratio between the neutral and polar fractions was 6: 1, both having linoleic acid as the main component.     

TOTAL LIPID PRODUCTION OF THE GREEN ALGA NANNOCHLOROPSIS SP. QII UNDER DIFFERENT NITROGEN REGIMES1

The green alga Nannochloropsis sp. QII was cultivated in media with sufficient and growth-limiting levels of nitrogen (nitrate). Nitrogen deficiency promoted lipid synthesis yielding cells with lipids comprising 55% of the biomass. The major lipids were triacylglycerols (79%), polar lipids (9%) and hydrocarbons (2.5%). The polar lipids consisted of a broad range of phospholipids, glycolipids and sulfolipids. Other lipids identified were pigments, free fatty acids, saponifiable and unsaponifiable sterol derivatives, various glycerides, a family of alkyl-1, 4-dioxane derivatives and a series of alkyl- and hydroxyalkyl-dimethyl-acetals. Experiments in which ¹⁴CO₂ was provided at different times in the growth cycle demonstrated that enhanced lipid biosynthesis at low nitrogen levels resulted principally from de novo CO₂ fixation.     

Hydrocarbons, Fatty Acids, and Lipids of Freshwater Grasses of the Potamogetonaceae Family

The composition of hydrocarbons, fatty acids, and of total, polar, and neutral lipids was studied in freshwater Potamogetonaceae grasses collected in two different regions of the Volga river. More than 40 fatty acids and hydrocarbons were separated and identified by chromato-mass spectrometry. The variability of lipid characteristics of plants of the same family is discussed.     

Lipid and hydrocarbon compositions of a collection strain and a wild sample of the green microalga Botryococcus

Lipid composition and hydrocarbon structure of two colonial green algae of the genus Botryococcus, i.e., a museum strain and a field sample collected for the first time from Lake Shira (Khakasia, Siberia), have been compared. Polar lipids, diacylglycerols, alcohols, triacylglycerols, sterols, sterol esters, free fatty acids and hydrocarbons have been identified among lipids in the laboratory culture. The dominant fraction in the museum strain was formed by polar lipids (up to 50% of the lipids) made up of fatty acids from C₁₂ to C₂₄. Palmitic, oleic, C₁₆ - C₁₈ dienoic and trienoic acids were the main fatty acids of the museum strain. Aliphatic hydrocarbons were found in the lipid of the museum strain. However, these amounted maximally to about 1% of the dry biomass at the end of exponential growth phase. The qualitative and quantitative compositions of FAs and hydrocarbons of the museum strain of Botryococcus, (registered at the Cambridge collection as Botryococcus braunii Kutz No LB 807/1 Droop 1950 H-252) differed from those of the Botryococcus strain described in the literature as Botryococcus braunii. The Botryococcus sp. found in Lake Shira is characterized by a higher lipid content (<40% of the dry weight). Polar lipids, sterols, triacylglycerols, free fatty acids and hydrocarbons have been identified among lipids in the field sample. The main lipids in this sample were dienes and trienes (hydrocarbons <60% of total lipid). Monounsaturated and very long chain monounsaturated fatty acids, including C_28:1 and C_32:1 acids, were identified in the Botryococcus found in Lake Shira. The chemo-taxonomic criteria allow us to unequivocally characterize the organism collected from Lake Shira as Botryococcus braunii, race A.