Response chromatographic fractions

A non-volatile contact pheromone contained in the cuticular wax of females elicits a wing-raising courtship response from males (Roth and Wilhs, 1952 Ishii, 1972). Nishida and co-workers obtained three active chromatographic fractions from hexane extracts of 224000 females. The major active component was identified as... 

Table I. Distribution of odor response in fractions obtained from C18, polyamide and PVP chromatographic separations of p-damascenone precursor from Concord grape extracts.

Strain TA98/1,8 DNP, exhibits a contrasting specificity for activation of the nitropyrenes. The mutagenicity of 1-nitropyrene is as great in this strain as it is in TA98, but the activities of all the multinitropyrenes are reduced. The relative response in the nitroreductase-deficient strains is a characteristic which can be used to identify the presence of these compounds in chromatographic fractions of diesel particle extracts. Figure 3 shows the way these strains were used with the TLC fractionation of diesel particle extract. 

When the bioactive dichloromethane extract of estrous urine was placed on a silica gel chromatography column and eluted with dichloromethane, ether, or benzene, the bioactivity was retained (Table 1 Figure 2). A total of 60 bioassays of these chromatographic fractions utilizing three bulls elicited 192 flehmen responses. Fractions eluted subsequently with other, more polar solvents showed no activity. Recovery was high in active fractions (Table 2). pH was manipulated several times, either to the acidic or to the basic pH biological activity was restored when pH was readjusted to 3.5-5.5 (Figure 1). 

Sotolon (4,5-dimethyl-3-hydroxy-2(5H)-furanone) and solerone (4-acetyl- y-butirrolactone) were claimed to be responsible for some aroma characteristic of flor sherries wines. These compounds are present only as traces, and are chemically unstable. A system of two gas chromatographs coupled with a four-port switching valve was used to quantitate these components without previous fractionation. The first chromatograph was equipped with an on-column injector, in order to avoid thermal degradation of sotolon in the heated injector, a DB-5 column and an FID. The second chromatograph was equipped with an on-column injector, a DB-1701 column and an FID. The method allowed quantification of solerone and sotolon at concentrations as low as a few ppb (29). 

The colorimetric procedure has been applied to each of the fractions isolated from the partition column. The response to the color test has allowed an accurate prediction of the general type of infrared spectra ultimately found. The color test has also been applied to fractions collected from the gas chromatograph. Of the major responses observed when the pyrethrum mixture is passed through the chromatograph, three of the components respond to the color test. At least two other pyrethrin-like compounds of long retention and small quantity also give the color test. No infrared data are available on these. 

Extraction of cultured G. toxicus. To prepare the harvested dinoflagellate cells (about 1 x 10 cells) for shipment from Hawaii to South Carolina, absolute methanol was added to effect a final concentration of approximately 25 (v/v). Upon receipt of the culture, additional methanol was added to attain a final concentration of 80% (v/v). After extraction at room temperature for J days, the suspension was clarified by centrifugation. The supernatant was dried and the resultant solids were weighed and resuspended in absolute methanol. The suspension was filtered and the filtrate designated as the crude dinoflagellate extract used in this study. Subsequent fractionation of this extract by HPLC (Higerd et al., manuscript in preparation) showed that the material responsible for toxicity eluted in a fraction well removed from the fraction that exhibited toxicity when extracts of either Pacific moray eel or Caribbean fish were chromatographed. In all cases, the body temperature depression effect was evident only in those fractions which also exhibited toxicity. 

Moved] Cranberry fruit of Early Black cultivar was fractionated chromatographically and fractions were analyzed for flavonoid content. The effects of the flavonoid fractions and ursolic acid, an abundant triterpenoid in cranberry peel, were assessed in two models of colon cancer and one model of breast cancer. Clonogenic soft agar assays were used to determine the effect of these compounds on tumor colony formation in HCT-116, HT-29 and MCF-7 cells. MTT and trypan blue assays were performed to assess their ability to inhibit tumor cell proliferation. TUNEL assays were performed to assess apop-totic response to the cranberry compounds. The proanthocyanidins inhibited tumor colony formation in HCT-116 and HT-29 cells in a dose-dependent manner, with greater effect on the HCT-116 cell line. Ursolic acid strongly inhibited tumor colony formation in both colon cell lines. These compounds also decreased proliferation in all three tumor cell lines with the HCT-116 cell line most strongly affected. (150 words)... 

Hypotensive activity. Essential oil, administered intravenously to dogs at a dose of 3 p,L/kg, was active. The ethanol (70%) extract, administered intravenously to dogs at a dose of 75 mg/kg, was active. There was a dip followed by rise in blood pressure° . Ethanol (80%) extract of the aerial parts, at a dose of 10 mg/kg, was not blocked by atropine. The extract did not inhibit pressor response of norepinephrine either . Ethanol (95%) extract of the seed, administered intravenously to dogs at a dose of 10 mg/kg, produced a transient effect that was blocked by atropine ". Petroleum ether fraction chromatographed and fraction eluted with chloroform, administered intravenously to rabbits at a dose of 0.80 mg/kg, was inactive. Methanol extract, administered intravenously to dogs and rabbits at a... 

Fractions of total addition products observed, calculated assuming equal gas chromatographic peak, area responses. b Extrapolated values for infinite pressure. c Small amounts of acetone formed are included. d Perhaps contains small amount, of diethyL ketone. 

Descending Paper Strip. First, individual fractions spaced five fractions apart were chromatographed. Definite GA3 response was observed in fraction 10 or the spike, weaker response in fraotion 15, and no response in the natural extract single fractions. To avoid the possibility of dissipating the fractions in individual runs below the detection limit, the remaining fractions were combined in groups... 

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