Chromatographic Estimation of Carotene in Feeds and Feed Ingredients

Photosynthesis in Aspen Bark

“…1) they were seen to be similar with maxima at 4200 A, 4400 A, and 4700 A and minima at 4300 A and 4600 A. Comparison of these' spectra with the absorption spectrum for ,B-carotene published by Cooley and Koehn (1950) suggests that ,B-carotene is not the most abundant of carotinoids present in these tissues. Judging from the total absorption at 4700 A, sun and shade leaves contained approximately equal quantities of carotinoids, south-facing bark about one and one-half times as much carotinoid pigment, and north-facing bark about twice as much carotinoid as leaves.…”

Colorimetric Standard for Carotene

“…The absorptivities of /3-carotene in mineral oil were compared with the absorptivities in 10% acetone in hexane because carotene probably is determined most frequently in the latter solvent (4,5,11,12). The absorptivities exhibited some variation in different solvents, as did the wave length of maximum absorbance (Figure 1, Table I).…”