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Guggulipid, the standardized product from the extraction of the ole-gum-resin from the Commiphora mukul plant, has been marketed as a hypolipidemic agent. The ketosteroids, cis- and trans-4,17(20)-pregnadiene-3,16-dione, known as E- and Z-guggulsterones, respectively, are the main ingredients in guggulipid. A liquid chromatographic method was developed for simultaneous determination of E- and Z-guggulsterones in guggulipid preparations using synthetic E- and Z-guggulsterone standards. Realtively low amounts of guggulsterones (E and Z) were found in commercial guggulipid preparations in comparison with the manufacturer's claim of 2.5%. The mixture of E- and Z-guggulsterones was extracted and separated on a Symmetry C18 reversed-phase column, with a mobile phase of acetonitrile–water (46 + 54, v/v) and detected at 242 nm. The retention times of E- and Z-guggulsterones are approximately 8 and 11 min, respectively. Assay quantitation was based on the calibration curve obtained from a mixture of synthetic standard E- and Z-guggulsterones. Experimental data on selectivity, linearity, accuracy, and recoveries are presented.

A collaborative study was conducted for determination of glucosamine in raw materials and dietary supplements containing glucosamine sulfate and/or glucosamine hydrochloride by high-performance liquid chromatography (HPLC) with N-(9-fluorenyl-methoxycarbonyloxy) succinimide (FMOC-Su) derivatization. Thirteen blind materials, one pair of which were duplicates, were tested by 12 collaborating laboratories. The test samples consisted of various commercial products, including tablets, capsules, drink mix, and liquids as well as raw materials, blanks, and those for spike recovery analyses. The tests with blank products and products spiked with glucosamine showed good specificity of the method. The average recoveries at spike levels of 100 and 150% of the declared amount were 99.0% with a relative standard deviation (RSD) of 2.1%, and 101% with an RSD of 2.3%, respectively. The test results between laboratories on each commercial product were reproducible with RSD values of no more than 4.0%, and the results were repeatable in the same laboratory with an average RSD of 0.7%. HorRat values ranged from 0.5 to 1.7 on both tests of spike recovery and reproducibility between laboratories on commercial products. The average determination coefficient of the calibration curves from the laboratories was 0.9995 with an RSD of 0.03%. All of the 12 collaborating laboratories succeeded in the study and none of their reported test results were outliers, partly indicating the robustness of the method. It is recommended that the method be accepted by AOAC INTERNATIONAL as Official First Action.

Commercial detergent additives to control water hardness are of three main types, sequestrant, precipitant or ion‐exchange builders. These builders lower the free hardness ion (Ca+2, Mg+2) concentration in a wash system by different mechanisms. An electrometric experimental method was used to evaluate the relative water hardness control performances of different builder‐types under conditions closely simulating those of detergent's end‐use. Experimental data for the following builders are presented: EDTA, NTA, STPP, PAA, CMOS, Na‐Citrate, Na2CO3 and type A zeolite. It is shown that the relative rankings of the various builders in water hardness control differ significantly with differences in use level concentration of the builder (0.005–0.100 gm per 100 ml). The application of the method to the selection of optimum molecular weight range of the newly emerging class of organic polymeric detergent builders like sodium polyacrylates (Na‐PAA) (Mw=2000−220,000) also is discussed.

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