Phospho-lipid fatty-acids

Microbial populations in landfill leachate-contaminated aquifers are dominated by bacteria (eubacteria and archaea), as shown by analysis of the phospho lipid fatty acids (PLFAs) (Ludvigsen et al, 1999). The total number of bacteria reported in landfill leachate plumes are in the range of 4 X 10" -1.5 X 10 cells g dry weight (dw) and the number of colony-forming units, hving cells, are in the range of 60-10 CFU g dw (Christensen et al, 2001). However, the large variation caused by different analytical methods and the fact that different types of aquifers were studied mask the difference in the number of... 

Incubation of a sample of phosphatidylglycerol with 0.5 M KOH in methanol at room temperature for 15 min will lead to complete cleavage of the fatty acid ester bonds with formation of methyl esters of long-chain fatty acids and sn-glycem-3-phospho-1 -.vu-glycerol. The progress of the reaction can be followed by loss of chloroform-soluble lipid phosphorus and the appearance of the methyl esters. This derivative can be further characterized by GC-MS. Examination of the water-soluble products will show that over 95% of the... 

The incorporation of [ H]-water into synthesized diacylglycerols was reduced even more than the incorporation into the other two lipid classes. As the sulfur-substituted fatty acids had only small effects on incorporation of pH]-water into cell monoacylgjyc-erols (data not shown), these data suggest that 3-thia fatty acids decreased TG-synfliesis by affecting the step before formation of diacylglycerols. The reduced incorporation into diacylglycerols, thus, may indicate that activity of the enzyme phosphatidate phospho-hydrolase could be affected. 

Neutral lipids these account for 40-60% of lipids in fresh latex but 82-86% of lipids in dry rubber. This share increase is due to the leaching of hydrophilic lipids (phospho- and glycolipids) as well as to the hydrolysis of fatty acid moieties from those hydrophilic lipids newly released free fatty acids thus join the neutral lipid family. Indeed, free fatty acids account for less than 2% of lipids in latex while they account for more than 20% of those extracted from dry rubber. Neutral lipids can be divided into fatty acids and unsaponiliables. 

Phytochemistry This species contained 1.67 % essential oils, the composition of which included aldehydes (Khalmatov 1964). According to Baser et al. (1997b), a total of 33 compounds were found in the essential oil, of which the principal components were p-cymene (27.2 %), thymol (15.1 %), carvacrol (12.5 %), and palmitic acid (2.9 %). A variety of neutral-, glyco- and phospho-lipids were isolated and identified from the leaves, and various free and bound fatty acids and carotenoids were quantified (Chernenko et al. 2002). 

The ocular surface is the domain of the mucosa-bonded immune system [24]. This system plays an important role in combating infections by killing micro-organisms. It consists of the lachrymal gland, conjunctiva and related structures. Besides immunoglobulins, enzymes and bactericidal components are present IgA, lysozyme, lactoferrin, lipocalins, cathelicidine and probably beta-defensins [25]. Lipocalin is considered the most important component in eliminating toxic (phospho)lipids and fatty acids from the ocular surface [26]. Elimination is necessary, otherwise only partial hydration of the corneal epithelium will occur, which could result in ulceration [27]. 

Phospho- lipids Free Fatty Acids Triglycer- ides... 

Fatty acid Total lipids Cholesterol esters Phospho- lipids Glycerides Free fatty acids... 

These fatty acid derivatives may be considered as complex lipids since they are formed of one fatty acid, a 3 -phospho-AMP linked to phosphorylated pantothenic acid (Vitamin F) and cysteamine. However, to simplify the nomenclature and taking into account their metabolism, we classify them within the big group of the fatty acids and their simple derivatives rather than within the complex and phosphorylated lipids. Long-chain acyl-CoA esters are substrates for a number of important enzymatic reactions and play a central role in the regulation of metabolism as allosteric regulators of several enzymes. 

Besides the inhibition of fatty acid biosynthesis the cyclohexane-1,3-dione derivates e.g. sethoxydim (Fig.3) also induce several other alterations of the plant composition and metabolism. Due to the herbicide-induced inhibition of fatty acid and biomembrane lipid formation, the development of functional chloroplasts, the formation of thylakoids and the chloroplast replication are also blocked (Lichtenthaler 1984, Lichtenthaler and Meier 1984) as well as the accumulation of chlorophylls and carotenoids (Lichtenthaler 1987, Lichtenthaler et al. 1987) but not their biosynthesis (Lichtenthaler 1987). This resulted in the formation of white leaf parts which are free of photosynthetic pigments. Furthermore, in herbicide-treated maize shoots the accumulation and biosynthesis of plastidic and cytoplasmic phospho- and glykolipids was blocked (Burgstahler and Lichtenthaler 1984 and Burgstahler 1985). The cyclohexane-1,3-dione derivatives block the... 

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