Lipids in hairy roots and non-Agrobacterium induced roots of Crambe abyssinica

Hairy root cultures of Crambe abyssinica were obtained through infection of leaves with two wild-type agropine strains of Agrobacterium rhizogenes. The efficiency of transformation was about 16 %. The presence of T-DNA from A. rhizogenes in the hairy roots genome was confirmed by PCR using specific primers for rolB and rolC genes. Selected clones of hairy roots and non-Agrobacterium induced roots from sterile cultures were used for analyses of acyl-lipids. The total amount of acyl-lipids per mg of dry weight was similar in both the non-Agrobacterium induced roots and the hairy roots in good physiological condition, and ranged from 38 to 53 nmol. However, in the clones which showed symptoms of ageing, the lipid content was severely reduced. Also the lipid composition of hairy roots appears to be similar to the composition of non-transformed roots. Polar lipids were the dominant class of lipids in both types of roots (about 75 %). Furthermore, we found diacylglycerols, free fatty acids (FFA), triacylglycerols, sterol esters, and an unidentified lipid class. The dominant fatty acids in the lipids of both types of roots were α-linolenic acid, palmitic acid, and linoleic acid (over 12 % of total FA). Among the lipids of both hairy roots and non-Agrobacterium induced roots of C. abyssinica, an unidentified FA was found (over 16 % of total FAs). The present study is the first example of establishment of hairy roots cultures of C. abyssinica. It also includes the first analysis of the lipids in hairy roots and non-Agrobacterium induced roots of this species.     

Fatty acid composition of total lipids from the needles of pine seedlings as related to boron availability

The effect of boron availability on the content of fatty acids (FA) in the total lipids of needles was investigated in two-year-old seedlings of Scots pine (Pinus sylvestris L.). The study was conducted in the forest nursery on the soil deficient in boron. Various rates of boric acid (0.01, 0.03, 0.1, 0.3, 1, 3, and 10 g/m²) were applied to soil three times throughout the growth period. When pine seedlings were supplied with extra boron, the lipid content of the seedling needles declined. The optimal boron supply elevated the content of saturated FA in total needle lipids mostly at the expense of palmitic acid, with a corresponding decline in the level of unsaturated FA and unsaturation index of FA owing to trienoic FA (mainly linolenic and hexadecatrienoic acids). At the same time, the level of monoenoic and to a lesser degree dienoic acids increased. When boron supply of the seedlings was not optimal, the content of unsaturated and low-molecular FA increased.     

Influence de la température sur la composition en acides gras du muscle abdominal de Palaemon serratus

The shrimp Palaemon serratus was acclimatized at 9°, 15°, 18° and 25°, the lipid and fatty acids composition of the abdominal muscle show important variations. In relation to wet weight, total lipid level and polyunsaturated fatty acids (18:2ω6; 20:5ω3; 20:3ω6; 22:6ω3), show an inverse relationship with temperature. On the other hand, an increase of fatty acid content in relation to total lipids is observed as temperature increases. Some mono-unsaturated fatty acids have a polyunsaturated-like behaviour, others a saturated-like behaviour.     

The effect of alterations in the physical state of the membrane lipids on the ability of Acholeplasma laidlawii B to grow at various temperatures

The physical state of the membrane lipids, as determined by fatty acid composition and environmental temperature, has a marked effect on both the temperature range within which Acholeplasma laidlawii B cells can grow and on growth rates within the permissible temperature ranges. The minimum growth temperature of 8 °C is not defined by the fatty acid composition of the membrane lipids when cells are enriched in fatty acids giving rise to gel to liquid-crystalline membrane lipid phase transitions occurring below this temperature. The elevated minimum growth temperatures of cells enriched in fatty acids giving rise to lipid phase transitions occurring at higher temperatures, however, are clearly defined by the fatty acid composition of the membrane lipids. The optimum and maximum growth temperatures are also influenced indirectly by the physical state of the membrane lipids, being significantly reduced for cells supplemented with lower melting, unsaturated fatty acids. The temperature coefficient of growth at temperatures near or above the midpoint of the lipid phase transition is 16 to 18 $\text{kcal}\text{mol}$, but this value increases abruptly to 40 to 45 $\text{kcal}\text{mol}$ at temperatures below the phase transition midpoint. Both the absolute rates and temperature coefficients of cell growth are similar for cells whose membrane lipids exist entirely or predominantly in the liquid-crystalline state, but absolute growth rates decline rapidly and temperature coefficients increase at temperatures where more than half of the membrane lipids become solidified. Cell growth ceases when the conversion of the membrane lipid to the gel state approaches completion, but growth and replication can continue at temperatures where less than one tenth of the total lipid remains in the fluid state. An appreciable heterogeneity in the physical state of the membrane lipids can apparently be tolerated by this organism without a detectable loss of membrane function.     

Lipid content and fatty acid composition of a marine-derived Trichoderma longibrachiatum strain cultured by agar surface and submerged fermentations

A marine-related Trichoderma longibrachiatum strain isolated from mussels in a farming shellfish area was investigated for total lipid (TL) production, total lipid fatty acids (TLFA), and phospholipid fatty acids (PLFA). Fungal biomass was produced from two different marine-like culture ways, on agar surface and submerged fermentations (ASF and SmF, respectively), allowing useful comparisons. ASF produced a rather higher biomass amount than SmF with similar TL content. All fatty acids (FA), identified by gas chromatography–mass spectrometry (GC–MS), were ranged from 14 to 30 carbon atoms. Similar FA compositions were found in TL and phospholipids (PL) from biomasses obtained by both fermentation systems, including oleic (up to 15.3% of total FA mixture for SmF, and 33.9% for ASF), linoleic (46.1% for SmF, and 40.3% for ASF) and palmitic (28.1% for SmF, and 19.1% for ASF) acids as major components. Regarding the most common FA, lipid class and FA profiles observed did not show marked differences with those available for some Trichoderma terrestrial species. Some 2-hydroxylated FA and a rather unusual series of C₁₈ unsaturated conjugated FA (CFA) were identified. In addition, fungal biomass production by ASF was found as an easy to operate process, especially for further screenings of marine-derived fungi.     

Biomass productivity and productivity of fatty acids and amino acids of microalgae strains as key characteristics of suitability for biodiesel production

Microalgae are discussed as an alternative source for the production of biofuels. The lipid content compared to cultivation time of used species is the main reason for any choice of a special strain. This paper reviews more analytical data of 38 screened microalgae strains. After the cultivation period, total content of lipids was analysed. The extracted fatty acids were quantified as fatty acid methyl esters by GC analysis. The amino acids were analysed by HPLC. Chlorella sp., Chlorella saccharophila, Chlorella minutissima and Chlorella vulgaris were identified as species with the highest productivity of fatty acids relevant to transesterification reactions. The components were mainly linoleic acid, palmitic acid and oleic acid. To increase productivity of highly saturated fatty acids, cultivation parameters light intensity and temperature were varied. In this manner, the ideal conditions for biodiesel production were defined in this publication.     

Mitochondrial activity,hemocyte parameters and lipid composition modulation by dietary conditioning in the Pacific oyster Crassostrea gigas

Several parameters can affect membrane lipid composition in bivalves, including diet. Although two fatty acids (FA) 22:6n-3 and 20:5n-3 are essential membrane components, they are sparingly synthesized by bivalves and must be obtained from their diet. Here, effects of dietary modifications of membrane lipid composition were studied at both cellular and subcellular levels in the oyster Crassostrea gigas. To this end, we compared oysters fed two monoalgal diets that differed markedly in their FA composition and a mix of both. As expected, algae impacted phospholipids, in particular 22:6n-3 and 20:5n-3, reflecting differences of dietary microalgae FA composition. Meantime, total saturated FA, total monounsaturated FA, total polyunsaturated FA and total non-methylene-interrupted FA varied little and phospholipid class composition was only slightly affected by diets. Measures made in hemocytes indicated that only mitochondrial membrane potential was affected by diets. Total ROS production as well as mitochondrial superoxide production did not differ with diet. There was no difference in phosphorylating (state 3) and non-phosphorylating (state 4) rates of oxygen consumption rates or in cytochrome c oxidase activity of mitochondria isolated from gills between the three diets. Similarly, neither cytochromes a, b, c or c ₁ content nor citrate synthase activities were changed, suggesting that number and morphology of mitochondria were not affected by dietary treatment. These results suggest that oysters could possess high homeostatic capabilities, at both cellular and subcellular levels, to minimize the effect of dietary FA and related membrane lipid FA modifications on mitochondrial functions. These capabilities could be a means to face variations in diet composition in their natural environment and to preserve important oyster physiological functions such as growth and reproduction.     

Temperature Affects the Use of Storage Fatty Acids as Energy Source in a Benthic Copepod (Platychelipus littoralis,Harpacticoida)

The utilization of storage lipids and their associated fatty acids (FA) is an important means for organisms to cope with periods of food shortage, however, little is known about the dynamics and FA mobilization in benthic copepods (order Harpacticoida). Furthermore, lipid depletion and FA mobilization may depend on the ambient temperature. Therefore, we subjected the temperate copepod Platychelipus littoralis to several intervals (3, 6 and 14 days) of food deprivation, under two temperatures in the range of the normal habitat temperature (4, 15°C) and under an elevated temperature (24°C), and studied the changes in FA composition of storage and membrane lipids. Although bulk depletion of storage FA occurred after a few days of food deprivation under 4°C and 15°C, copepod survival remained high during the experiment, suggesting the catabolization of other energy sources. Ambient temperature affected both the degree of FA depletion and the FA mobilization. In particular, storage FA were more exhausted and FA mobilization was more selective under 15°C compared with 4°C. In contrast, depletion of storage FA was limited under an elevated temperature, potentially due to a switch to partial anaerobiosis. Food deprivation induced selective DHA retention in the copepod’s membrane, under all temperatures. However, prolonged exposure to heat and nutritional stress eventually depleted DHA in the membranes, and potentially induced high copepod mortality. Storage lipids clearly played an important role in the short-term response of the copepod P. littoralis to food deprivation. However, under elevated temperature, the use of storage FA as an energy source is compromised.     

Large fluxes of fatty acids from membranes to triacylglycerol and back during N-deprivation and recovery in Chlamydomonas

Microalgae accumulate triacylglycerol (TAG) during nutrient deprivation and break it down after nutrient resupply, and these processes involve dramatic shifts in cellular carbon allocation. Due to the importance of algae in the global carbon cycle, and the potential of algal lipids as feedstock for chemical and fuel production, these processes are of both ecophysiological and biotechnological importance. However, the metabolism of TAG is not well understood, particularly the contributions of fatty acids (FAs) from different membrane lipids to TAG accumulation and the fate of TAG FAs during degradation. Here, we used isotopic labeling time course experiments on Chlamydomonas reinhardtii to track FA synthesis and transfer between lipid pools during nitrogen (N)-deprivation and resupply. When cells were labeled before N-deprivation, total levels of label in cellular FAs were unchanged during subsequent N-deprivation and later resupply, despite large fluxes into and out of TAG and membrane lipid pools. Detailed analyses of FA levels and labeling revealed that about one-third of acyl chains accumulating in TAG during N-deprivation derive from preexisting membrane lipids, and in total, at least 45% of TAG FAs passed through membrane lipids at one point. Notably, most acyl chains in membrane lipids during recovery after N-resupply come from TAG. Fluxes of polyunsaturated FAs from plastidic membranes into TAG during N-deprivation were particularly noteworthy. These findings demonstrate a high degree of integration of TAG and membrane lipid metabolism and highlight a role for TAG in storage and supply of membrane lipid components.

In Chlamydomonas, about a third of triacylglycerol (TAG) made during nitrogen deprivation is derived from preexisting membranes, and most membranes made after resupply are derived from TAG.     

Comparison of fatty acid contents and composition in major lipid classes of larvae and adults of mosquitoes (Diptera: Culicidae) from a steppe region

Emerging aquatic insects, including mosquitoes, are known to transfer to terrestrial ecosystems specific essential biochemicals, such as polyunsaturated fatty acids (PUFA). We studied fatty acid (FA) composition and contents of dominant mosquito populations (Diptera: Culicidae), that is, Anopheles messeae, Ochlerotatus caspius, Oc. flavescens, Oc. euedes, Oc. subdiversus, Oc. cataphylla, and Aedes cinereus, inhabited a steppe wetland of a temperate climate zone to fill up the gap in their lipid knowledge. The polar lipid and triacylglycerol fractions of larvae and adults were compared. In most studied mosquito species, we first found and identified a number of short‐chain PUFA, for example, prominent 14:2n‐6 and 14:3n‐3, which were not earlier documented in living organisms. These PUFA, although occurred in low levels in adult mosquitoes, can be potentially used as markers of mosquito biomass in terrestrial food webs. We hypothesize that these acids might be synthesized (or retroconverted) by the mosquitoes. Using FA trophic markers accumulated in triacylglycerols, trophic relations of the mosquitoes were accessed. The larval diet comprised green algae, cryptophytes, and dinoflagellates and provided the mosquitoes with essential n‐3 PUFA, linolenic, and eicosapentaenoic acids. As a result, both larvae and adults of the studied mosquitoes had comparatively high content of the essential PUFA. Comparison of FA proportions in polar lipids versus storage lipids shown that during mosquito metamorphosis transfer of essential eicosapentaenoic and arachidonic acids from the reserve in storage lipids of larvae to functional polar lipids in adults occurred.     

Fatty acids of sponges from the Sea of Okhotsk

The fatty acid (FA) composition of Demospongiae species from the Sea of Okhotsk was studied. Fifteen sponge species were investigated for the first time, and the previously studied species Desmacella rosea and Myxilla incrustans were reexamined for their FA composition. Gas chromatography-mass spectrometry revealed 150 different fatty acids, of which 15 have not been identified in sponge lipids previously. The relative content of saturated FAs varied from 7.6 in Melonachora kobjakovae to 29.6% in Amphilectus digitata, with an average of 14.6% of total FAs. The relative content of monoenic FAs ranged from 12.8 in T. dirhaphis to 27.0% in Polymastia sp., with an average of 20.6% of total FAs. Non-methylen-interrupted, primarily unsaturated Δ5,9-FAs contributed a significantly to the amount of polyunsaturated fatty acids of sponges; this being a distinguishing feature of the FA composition of the investigated group of organisms.     

Effect of rate of increase of water temperature on sensitivity of fish digestive glycosidases to action of copper and zinc

There was established an increase of sensitivity of glycosidases of intestinal mucosa of juvenile goldfish Carassius auratus, carp Cyprinus carpio, roach Rutilus rutilus, and common perch Perca fluviatilis to action in vitro of heavy metal ions (copper and zinc at concentrations of 0.1–25 mg/l) at heating of water at the summer period. The inhibitory effect of copper and zinc ions as a rule was higher at the heating rate of 50°C/h than at the rate of 4°C/h. The perch glycosidases were less sensitive to the elevation of temperature and to effect of the copper ions as compared with the enzymes of the carp species.     

Changes in the fatty acid composition of symbiotic dinoflagellates from the hermatypic coral <Emphasis Type="Italic">Echinopora lamellosa</Emphasis> during adaptation to the irradiance level

The composition of fatty acids (FAs) of symbiotic dinoflagellates isolated from the hermatypic coral Echinoporal lamellosa adapted to the irradiance of 95, 30, 8, and 2% PAR was studied. Polar lipids and triacylglycerols (TAG) differed between them in FA composition. Polar lipids were enriched in unsaturated FAs, whereas TAG, in saturated FAs. Light exerted a substantial influence on the FA composition in both polar lipids and TAG. The elevation of irradiance resulted in the accumulation of 16:0 acid in both lipid groups and 16:1(n-7) acid in TAG. It seems likely that de novo synthesis of 16:0 acid occurred actively in the cells of symbiotic dinoflagellates in high light. Since these processes are energy-consuming ones, they utilize excessive energy. When light intensity declined, 18:4(n-3) and 20:5(n-3) acids accumulated in polar lipids, which was accompanied by the increase in the content of chlorophyll a in the cells of zooxanthellae, whereas the levels of 22:6(n-3) and 20:4(n-6) acids reduced. Although the relative content of particular FAs varied substantially in dependence of irradiance, the balance between the sum of saturated and unsaturated FAs changed insignificantly. We concluded that the role of photoadaptation could not be limited only to changes in the degree of lipid unsaturation and membrane fluidity. It is supposed that light-induced changes in the FA composition reflect the interrelation between photosynthesis and FA biosynthesis.     

Characteristics of <Emphasis Type="Italic">Pseudomonas aurantiaca</Emphasis> DNA supramolecular complexes at various developmental stages

Differences in viscoelasticity (η) and molecular mass (M) values, as well as in the fatty acid profile of lipids in DNA supramolecular complexes (SC), isolated from Pseudomonas aurantiaca cultures at the exponential and stationary growth phases, were established for the first time. Typical characteristics of DNA SC from actively growing cells were the following: η = 315 ± 15 dl/g, M_DNA = 39 × 10⁶ Da, C_16:0 > C_18:0 > C_18:1 present as basic fatty acids (FA) in a pool of loosely DNA-bound lipids; the tightly DNA-bound lipid fraction consisted of only two acids C_18:0 > C_16:0. Significantly higher values of viscoelasticity η = 779 ± 8 dl/g and M_DNA = 198 × 10⁶ Da were observed for DNA SC of the stationary phase cells; one more FA, C_14:0, was detected in the loosely bound lipid fraction, while lipids tightly bound to DNA contained mainly C_16:0 > C_18:1 > C_18:0 > C_14:0 FA. The content of saturated FA in the DNA-bound lipids in the stationary phase cells was twice as high than in the exponential phase cells. The fraction of tightly bound lipids from the stationary phase cells contained nine times more unsaturated fatty acids than the fraction from proliferating cells. These differences in FA composition of DNA-bound lipids demonstrate the importance of lipids for the structural organization and functioning of genomic DNA during bacterial culture development.     

Light,temperature and nitrogen starvation effects on the total lipid and fatty acid content and composition ofSpirulina platensis UTEX 1928

The total lipid and fatty acid content ofSpirulina platensis UTEX 1928 was 7.2 and 2.2% respectively of cellular dry weight under controlled conditions supporting high growth rates. With increases in irradiance from 170 to 870 μmol photon m^?2 s^?1, growth rate increased, total lipid decreased, and fatty acid composition was unaffected. At 1411 μmol photon m^?2 s^?1, total lipid increased slightly and percent composition of the fatty acid gamma linolenic acid increased. Growth and total lipid content ofS. platensis were affected by changes in growth temperature from 25 to 38 °C. With increased growth rate, total lipid content increased. This suggests that the storage of carbon increases at temperatures supporting high growth rates. The degree of saturation increased with temperature. Although the percent composition of gamma linolenic acid was higher at lower growth temperature, production was still primarily a function of growth rate. The effect of temperature on fatty acid content and degree of saturation was of secondary importance. Nitrogen starvation increased total lipid content but decreased fatty acid content as a percentage of dry weight; composition of the fatty acids was unaffected. N-starvation appeared to suspend synthesis of long chain fatty acids inS. platensis, suggesting that some other compound stores fixed carbon when nitrogen is limiting. It was concluded that fatty acid production inS. platensis is maximized by optimizing culture conditions for growth.     

Tissue-Specific Fatty Acids Response to Different Diets in Common Carp (Cyprinus carpio L.)

Fish depend on dietary fatty acids (FA) to support their physiological condition and health. Exploring the FA distribution in common carp (Cyprinus carpio), one of the world''s most consumed freshwater fish, is important to understand how and where FA of different sources are allocated. We investigated diet effects on the composition of polar and neutral lipid fatty acids (PLFA and NLFA, respectively) in eight different tissues (dorsal and ventral muscle, heart, kidney, intestine, eyes, liver and adipose tissue) of common carp. Two-year old carp were exposed to three diet sources (i.e., zooplankton, zooplankton plus supplementary feeds containing vegetable, VO, or fish oil, FO) with different FA composition. The PLFA and NLFA response was clearly tissue-specific after 210 days of feeding on different diets. PLFA were generally rich in omega-3 polyunsaturated FA and only marginally influenced by dietary FA, whereas the NLFA composition strongly reflected dietary FA profiles. However, the NLFA composition in carp tissues varied considerably at low NLFA mass ratios, suggesting that carp is able to regulate the NLFA composition and thus FA quality in its tissues when NLFA contents are low. Finally, this study shows that FO were 3X more retained than VO as NLFA particularly in muscle tissues, indicating that higher nutritional quality feeds are selectively allocated into tissues and thus available for human consumption.     

Temperature-induced specific lipid desaturation in the thermophilic cyanobacterium Synechococcus vulcanus

Cyanobacteria desaturate fatty acids in the membrane lipids in response to decrease in temperature. We examined the changes in lipid and fatty acid composition in the thermophilic cyanobacterium Synechococcus vulcanus, which is characterized by an optimum growth temperature of 55°C. During temperature acclimation to 45°C or 35°C, the cells synthesized oleic acid at the expense of stearic acid in the membrane lipids. Unlike mesophilic cyanobacteria, S. vulcanus did not show any significant adaptive desaturation in the galactolipids monogalactosyl diacylglycerol and digalactosyl diacylglycerol, that comprise 50% and 30% of total membrane lipids, respectively. The major changes in fatty acid unsaturation were observed in the sulfolipid sulfoquinovosyl diacylglycerol.     

Assimilation and biosynthesis of lipids in Arctic Calanus species based on feeding experiments with a C labelled diatom

The dominant Arctic Ocean and North Atlantic copepods Calanus hyperboreus, Calanus glacialis, and Calanus finmarchicus were collected in the Greenland Sea and fed ¹³C labelled diatom Thalassiosira weissflogii to follow the transfer and assimilation of carbon, lipid, and individual fatty acids and alcohols. The diatom was grown with ¹³C for 3 to 5 days and fed then to the copepods. During the feeding period of 14 days, total carbon increased in the copepodite stages V of C. hyperboreus and C. finmarchicus, whereas carbon remained almost constant in C. glacialis females. However, total lipid increased in all species and stages. Highest lipid accumulation occurred in C. hyperboreus in which nearly all lipids were exchanged already after 11 days of feeding. In the other species lipid accumulation made up between 22% (C. finmarchicus) and 45% of total lipid (C. glacialis). The proportion of wax esters was high ranging from 76% of total lipid in C. glacialis to 92% in C. finmarchicus. The fatty acid composition of the alga was dominated by 16:1(n-7), 16:0, 20:5(n-3), and 22:6(n-3). The composition of the copepods was similar because of feeding already on diatoms in the field. In addition, the monounsaturated fatty acids and alcohols, 20:1(n-9) and 22:1(n-11), were major components of the copepod lipids. During the feeding period the highest ¹³C labelling was always found in the C₁₆ polyunsaturated fatty acids and in the 16:1(n-7) alcohol. Because these components occurred only in trace amounts in the copepods they totally originated from the diet explaining the high labelling. It is noteworthy that the 16:1(n-7) alcohol originated only from the corresponding dietary and not from the abundant internal fatty acid. The long-chain monounsaturated fatty acids and alcohols, 20:1(n-9) and 22:1(n-11), are not existent in phytoplankton and have to be produced de novo. They were less labelled in the smaller species but highly ¹³C enriched in C. hyperboreus. Although dietary fatty acids were generally retained by the copepods it seems that fatty acids or even lipids were selectively accumulated and turned over due to bodily requirements, and thus, essential polyunsaturated fatty acids were preferentially retained. During feeding mixing, accumulation, and exchange of internal and dietary fatty acids and alcohols occurred as well as utilisation of lipids from both sources for metabolic requirements. The differences in lipid assimilation fit to the different life strategies of the copepods.     

Lipid class and fatty acid compositions of the zoanthid Palythoa caesia (Anthozoa: Hexacorallia: Zoanthidea) and its chemotaxonomic relations with corals

Lipid class and fatty acid (FA) compositions of the zoanthid Palythoa caesia from the South China Sea (Vietnam) were determined and compared with those of zooxanthellate reef-building and soft corals from the same region to clarify chemotaxonomic relations between zoanthids and corals. Total lipids of P. caesia and corals were formed by the same lipid classes. The lipids of P. caesia contained specific for cnidarians monoalkyldiacylglycerols and phosphonolipids. The proportion between reserve and structural lipid classes of P. caesia was similar to that of alcyonarians (soft corals), but significantly differed from reef-building corals. This similarity may be caused by the similar energy budget of cnidarian colonies without hard exoskeleton. The distribution of polyunsaturated FAs (PUFAs), such as 22:4n-6 and 22:5n-3, indicated pathways of biosynthesis of PUFAs in Palythoa to be closer to those in reef-building corals than in soft corals. The differences in the profiles of common FAs between P. caesia and reef-building corals were showed. Zoanthid lipids contained rare Δ5,9 non-methylene-interrupted (NMI) PUFAs (with two and three double bounds), which probably originated from microorganisms associated with P. caesia. Trienoic acids Δ5,9,15–24:3 and Δ5,9,17–24:3 were found in Palythoa for the first time. NMI PUFAs, as well as total FA profile, can be used for chemotaxonomy of Palythoa.     

Oily yeasts as oleaginous cell factories

Oily yeasts have been described to be able to accumulate lipids up to 20% of their cellular dry weight. These yeasts represent a minor proportion of the total yeast population, and only 5% of them have been reported as able to accumulate more than 25% of lipids. The oily yeast genera include Yarrowia, Candida, Rhodotorula, Rhodosporidium, Cryptococcus, Trichosporon, and Lipomyces. More specifically, examples of oleaginous yeasts include the species: Lipomyces starkeyi, Rhodosporidium toruloides, Rhodotorula glutinis, and Yarrowia lipolytica. Yeast do exhibit advantages for lipid production over other microbial sources, namely, their duplication times are usually lower than 1 h, are much less affected than plants by season or climate conditions, and their cultures are more easily scaled up than those of microalgae. Additionally, some oily yeasts have been reported to accumulate oil up to 80% of their dry weight and can indeed generate different lipids from different carbon sources or from lipids present in the culture media. Thus, they can vary their lipid composition by replacing the fatty acids present in their triglycerides. Due to the diversity of microorganisms and growth conditions, oily yeasts can be useful for the production of triglycerides, surfactants, or polyunsaturated fatty acids.