Extractability testing Subject

Ginseng extracts have also been shown to modulate the immune responsiveness of human leukocytes in vitro. For example, extracts from P. ginseng were reported to increase NK cell function and ADCC in PBMC from both healthy and immunocompromised individuals [18]. In addition, similar extracts and their degradation products displayed anti-complement activity [46]. In contrast to the mouse data described above, a standardized ginseng extract (Gerimax) by itself (no inflammatory stimulus) induced the production of IL-12 (but not IL-10) by PBMC from healthy test subjects [47],... 

In this connection it must be borne in mind that in some of these extraction tests on naturally coloured and raw cotton, flax, wool, hair, etc, an appreciable quantity of yellowish-brown colouring matter is removed, and that raw silks of a natural yellow or green colour exhibit special behaviour if subjected to some of these tests, eg, to treatment with concentrated acids ... 

Examination on the production of brassinosteroid-like active substances. The cells were extracted with methanol, and the NE fractions of the extracts were subjected to bioassay using the rice lamina inclination test by the same... 

Extractive tests based on various simulants are offered in such compendial standards (past and/or present) as USP, EP, JP, WHO, and BP. These tests, in which extracted solution(s) are subject to chemical analysis and biological assessment, give information on the materials extracted and the general safety of the extracted solution. Although attempts are being made to standardise methodology worldwide, there are currently differences between the requirements in the USA, Europe, Japan, etc. Some of these are summarised in Table 8.4 in the EP 1989 they are covered under VI.1.2. etc. 

In order to isolate the actual promoter(s), the crude extracts were further resolved by a series of chromatographic separations. The methanol soluble extract was subjected to LH-20 size exclusion chromatography (methanol). Twelve fractions eluted and almost all activity was concentrated in fraction B . TLC analysis indicated that this material was identical to the G fraction previously tested. Table 7 shows the taxoid titers of P. raistrickii cultures grown with these column fractions (experiment 8-50). The results show taxol and taxane titers of combined mycelial and filtrate extracts minus background. Fungi were grown for 6 days, shaken at 200 rpm, room temperature, in M-l-S broth (soytone sucrose and yeast). All results were extrapolated to ng/L. 

Chemical analysis of the freeze-dried tissues (FDT) was carried out by extracting FDT samples with methanol in a blender. Water was added to the methanol extract and the aqueous methanol solution was defatted with SkellySolve F prior to partitioning with chloroform. Residue from the chloroform extracts was examined by TLC on silica gel. In some tests, the chloroform extracts were subjected to column cleanup before TLC examination... 

The method described herein for the analysis of volatile organics is a modified procedure of that described by Schuberth (28). Aliquots of 10-20 mL of blood are obtained from the test subjects with the use of a Vacutainer and collected into 10-mL tubes containing 15 mg of ethylenediaminotetraacetic acid (EDTA) and 100 mg of NaF as anticoagulant and preservative, respectively. The samples are then stored at 4°C. Aliquots of 1.5 mL of blood are then added to a headspace vial containing 1.8 g of NaCl. Headspace extraction is done at a bath temperature of 50°C and an equilibrium time of 30 min. 

Natural vanilla extract is subjected to a wide range of tests to ensure its authenticity. These include ... 

A similar approach has been used to identify insect feeding deterrents (Escoubas et al. 1992). Here, chemical separations of plant extracts are carried out on silica thin-layer chromatography plates. After the separation is complete and solvent is allowed to evaporate from the plates, a thin layer of agar-based artificial diet is poured over the plate. Chemical compounds from the plate then diffuse into the artificial diet. Test subjects then are allowed to feed on the diet-coated plates. Presumably, the areas that are not eaten contain antifeedants, which can later be identified chemically. 

Physical and chemical tests of the final product may need to address two concerns (1) whether the solidified waste exhibits any RCRA defined toxicity characteristics or could be delisted and (2) the potential long term fate of treated materials in the disposal environment. Three tests are available which address the first concern. These are the Extraction Procedure (EP Tox) (40 CFR 261, Appendix II, 1980) and the Toxicity Characteristic Leaching Procedure (TCLP) (40 CFR 261, Appendix II, 1986), and the Multiple Extraction Procedure Test (40 CFR 261, Appendix II, January 1989). It is important to note that these tests are not indicators of expected leachate quality but of potentials. A solidified product which cannot pass the appropriate test (EP Tox or TCLP) would be subject to classification as a hazardous waste. 

Experimental evidence in humans is based upon intervention studies with diets enriched in carotenoids or carotenoid-contaiifing foods. Oxidative stress biomarkers are measured in plasma or urine. The inhibition of low density lipoprotein (LDL) oxidation has been posmlated as one mechanism by which antioxidants may prevent the development of atherosclerosis. Since carotenoids are transported mainly via LDL in blood, testing the susceptibility of carotenoid-loaded LDL to oxidation is a common method of evaluating the antioxidant activities of carotenoids in vivo. This type of smdy is more precisely of the ex vivo type because LDLs are extracted from plasma in order to be tested in vitro for oxidative sensitivity after the subjects are given a special diet. 

Extraction procedures must be adjusted when separated anthocyanins will be tested in biological studies. We have found that the types of acids used for anthocyanin extraction as well as their residual concentrations in the final extract may affect the results obtained from biological tests. The growth inhibitory effect of anthocyanins on HT29 (human colonic cancer) cells may be overestimated if the residual acid in the extract exerts a toxic effect on the cells. Acetic acid residues in anthocyanin extracts showed less toxicity to HT29 cells than hydrochloric acid when samples were prepared under the same extraction procedure and subjected to the same tests on HT29 cells. In addition, the procedure to remove acids affected the acid residual concentration as well in final anthocyanin extracts, with lyophilization being more successful than rotary evaporation. 

For this GC determination with ECD, use only a sample test solution which has been adequately subjected to cleanup by silica gel column chromatography or by other means. Eluates 4 and 5 frequently contain considerable amounts of co-extractives, which may affect the evaluation of the chromatograms. 

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