Purpose standards

Thus, a combination of coconut (C10 C12) and tallow (C16 -C1X) fatty acids is most suitable from the viewpoint of providing a balance in lathering attributes to deliver consumer-acceptable lather. Commonly accepted ratios of these soap feedstocks are 80-85 percent tallow and 15-20 percent coconut oil for standard purpose bars and 60-70 percent tallow, 30-40 percent coconut oil for the higher lathering bar-soap products. Cleansing bars formulated with free fatty acids (superfatting) improves the quickness of lather generation and provides an open bubbly foam. Commonly accepted levels... 

It can be shown that r" + is a constant, independent of the choice of the pair of planes. An infinite set of such pairs of radii is possible, so this is not a useful means of description. For standardization purposes the first plane is rotated around the normal till the radius of curvature in that plane has a minimum, l.e. till the strongest curvature has been met. The other radius then has a maximum. The two radii, obtained in this way are the principal radii of curvature, R, and the corresponding curvatures Cj = R and = R are the principal curvatures. 

The most thorough validation procedure is required for test method standardization purposes. The work needed is considerable and covers proficiency testing, the determination of factors affecting the uncertainty, measuring range, etc. 

Important to the performance of substrate assays is the problem of availability of well-defined enzymes fiir standardization purposes. The noted variability within and among the currently available commercial rei ents fiir thrombin. Factor Xa, and kallikrein as well as the observation that denatured or altered enzymes lose more of their biological clotting activity than their amidase potency illustrates this problem. Hemker has pointed out two examples of this latter concern vidiere an apparently fiilse higher level of activity was indicated by the substrate assay method (H3). With thrombin it... 

A full description of the methods is usually not required for proficiency tests or for standardization purposes it is, however, an essential element when the performance of a laboratory or a method has to be evaluated, e.g. in the frame of step-by-step projects. The BCR has elaborated reporting forms for the description of various types of analytical methods for the certification of inorganic and organic parameters (see Appendix), which may be used as a basis to prepare forms for all types of interlaboratory studies. The questions are intended to remind the participants which important parameters are to be taken into consideration (possibly affecting the quality of the final result). These forms can also be used in technical discussions with other participants when differences in the results are noticed. Finally, they may constitute the basis for the method description in the certification reports. 

The SCOR process reference model was established by the Supply Chain Council (SCC) in 1996 for standardization purposes. The model describes, characterizes, and evaluates acomplex management process. Such a model builds on the concepts of business process reengineering (BPR), benchmarking, and process measurement by integrating these techniques into a cross-functional framework. 

The ketoalkenyns cannot be detected in . angustifolia and . purpurea roots. So they are suitable markers for the identification of preparations from . pallida roots. They can be analysed by TLC (silica gel toluene-ethylacetate 7 3 detection anisaldehyde/sulfuric acid) or (better) by HPLC (RP 18 solvent gradient 40-80% acetonitrile/water flow 1.0 ml/min detection 210 nm) (Figs. 7 and 8) [31]. Since they are not stable, they are not suitable for standardization purposes. 

Roots of Echinacea purpurea contain up to 0.2% essential oil [4, 14,15, 21, 67, 69, 74]. According to Becker [75] and Martin [76] it is composed of 2.1% caryophyl-lene, 0.6% humulene and 1.3% caryophyllene epoxide. Heinzer et al. [14] have analyzed the essential oil by gas chromatography-mass spectrometry (GC-MS) and found compounds of the type dodeca-2,4- dien-l-yl-isovalerate, as well as palmitic and linolenic acid, vanillin, p-hydroxycinnamic acid methyl ester and germacrene D, which had already been reported by Bohlmann and Hoffmann [27] for the aerial parts of the plant. Nevertheless, . purpurea roots are not a typical essential oil drug, and therefore analysis of the essential oil has not been used often for standardization purposes of phytopreparations. However, gas chromatography of the essential oil can be used for the discrimination of the species (see Fig. 1) [14]. 

With the aid of HPLC analysis and photodiode array detection (DAD), the different types of alkamides can easily be identified by their different UV-spectra [30]. Hence, the roots of . purpurea and . angustifolia can clearly be discriminated by DAD-HPLC of these lipophilic constituents (see Figs. 2 and 9). Quantitative determination in phytopreparations is also possible by HPLC. The roots of E purpurea were found to contain 0.004-0.039% dodeca-2 ,4 ,8Z,10 /Z-tetraenoic acid isobutylamide [30]. HPLC analysis of the alkamides in extracts of Echinacea purpurea roots would therefore be especially suitable for standardization purposes. An RPLC procedure published recently for the quantitative analyses of alkamide levels in Echinacea purpurea extracts [80] is suspected of leading to elevated levels of alkamides and should therefore only be applied after careful recalibration. 

The major anthocyanins of . purpurea (and . pallida) have been identified as cyanidin-3-0-(p-D-glycopyranoside) and cyanidin-3-0-(6-0-malonyl-p-D-glyco-pyranoside) [105]. So far, they do not play any role for standardization purposes. 

For standardization purposes, adequate marker compounds need to be selected in order to base quality control on therapeutically relevant constituents. Compounds which specifically occur in Echinacea should be preferred. Accordingly, glycin-betain, coumaric acid or fructofuranosides may not be well suited for a specific characterization of Echinacea products. 

Echinacoside is a typical and major compound of E. angustifolia and E. pallida roots. It may be used as a marker compound, but as far as we know, it does not possess any immunomodulatory relevance. Nevertheless, it may be the best suited constituent in E. pallida roots for standardization purposes. However, ketoalkenyns should not be neglected and a constant pattern of these compounds should be guaranteed as well. Determination of two compounds (one polar and one lipophilic) would also demonstrate that the extract has been properly prepared. 

For commercial purposes it is useful to standardize the alpha acids content of extracts to 15, 30 or 60 %. Glucose syrup has been used as diluent, but phase demixing, when occurring, may be masked by the dark colour of the extract paste. This has been the cause of great difficulties. Water extracts of the hop extract residue (phenolics, salts, coloured matter, etc.) are also used for standardization purposes. Extracts of various content can also be mixed in the correct proportions to achieve the required result. It is recommended to check the real alpha acids value of an extract, because an error of only 10-20 % can have disastrous effects on the level of beer bitterness. 

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