In a normal distribution, 68.2% of all scores cluster around the mean within approximately 1 standard deviation, 95.4% within approximately 2 standard deviations, and 99.7% within approximately 3 standard deviations.
Phospholipid-derived fatty acids (PLFA) are widely used in microbial ecology as chemotaxonomic markers of bacteria and other organisms.Phospholipids are the primary lipids composing cellular membranes. Phospholipids can be saponified, which releases the fatty acids contained in their diglyceride tail.ach phospholipid consists of a polar hydrophilic head (red) and two hydrophobic fatty acid tails. The fatty acid structure affects the bilayer structure. Fatty acids with an unsaturated tail (blue) disrupt the packing of those with only saturated tails (black).
Of particular interest are âpolyunsaturated fatty acidsâ. Within the family of polyunsaturated fatty acids (PUFAs), there are two different groups: the âomega-3-fatty acids âand âomega-6-fatty acidsâ (1). Both are considered essential fatty acids because they cannot be synthesized by humans. The parent fatty acid of the omega-3 series is alpha-linolenic acid (ALA). The long-chain omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), can be synthesized from ALA, although conversion rates are very low, especially for DHA.