Bract removal

First is the application of substances under study in fractionated lanolin as 5 microliter droplets to sear left after bract removal. A critical condition for sensitivity in the bioassay is the length of the stem which has to be approximately 5-10 mm long and must be at the early stage of the logarithmic phase of growth. Application in lanolin is important because it appears that BRst must be in continual contact with the plant. When BRst are removed, or applied in water, ethanol or another solution, the concentration of... 

Acetone precipitated CDE and CBE caused minimal contraction of the rat stomach smooth muscle. The supernatant retained most of the active substance (64). Butanol, however, did extract the active components of both CBE and CDE ( ). Ethyl acetate, which will extract 5HT from an aqueous solution ( ), was unsuccessful in removing the active components. These findings are in agreement with Russell t l. (66), who used this procedure to demonstrate that the active component of bract was "5HT-like." The active agent(s) in extracts of the dust and bract were demonstrated to have a molecular weight below 20,000. 

Bract and leaf trash materials are difficult to remove from cotton during ginning and comprise between % and 1% of the weight of a typical bale of strict low middling cotton ( ). Thus bract and leaf trash components are present in sufficiently large amounts in raw cotton to function as botanical carriers of the suspect byssinotic agent(s). 

B. Substances under study were applied in 5 microliter drops of fractionated lanolin to the sear left after the removal of bract from the base of the second internode. A crucial condition for sensitivity in the bioassay is the length of the second internode which has to be about 2 mm long at the time of BRst application. 

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