| 释义 |
phæophorbide Biochem.|fiːəʊˈfɔːbaɪd|
Also pheo-.
[ad. G. phäophorbid (Willstätter & Stoll 1911, in Ann. d. Chem. CCCLXXVIII. 25), f. as phæophytin + Gr. ϕορβή pasture, food: see -ide.]
Either of two compounds (orig. not distinguished) formed by the action of a strong acid on chlorophyll or phæophytin, having the structure of the latter except for the replacement of the phytol group by a hydrogen atom: phæophorbide a, HOOC·C32H32N4O·COOCH3, or phæophorbide b, HOOC·C32H30N4O2·COOCH3. Also, an ester of one of these compounds (as phæophytin).
1911Chem. Abstr. V. 873 The following nomenclature is now adopted: for the free tricarboxylic acid, the basis of chlorophyll, the name chlorophyllin is retained, the monomethyl ester is called chlorophyllide and the deriv. free from Mg, pheophorbide. 1950J. Bonner Plant Biochem. xxx. 470 Hydrolysis of pheophytin with stronger acid removes the phytol group to yield pheophorbides a and b, which are both monocarboxylic acids and which can be esterified..to yield the alkyl pheophorbides. 1956I. L. Finar Org. Chem. II. xix. 697 These phytyl phæophorbides are also known as phæophytins a and b. Ibid. 702 When phytyl phæophorbide-a..is hydrolysed with acid, the phytyl group is removed to form phæophorbide-a. 1963R. P. Dales Annelids ii. 56 The intestine..is apparently absorptive. It is this region that has a deep green colour, just as that of Chaetopterus has, and for the same reason, for in both the colour is due to phæophorbides—breakdown products of chlorophylls presumably derived from the food. 1975Nature 24 Jan. 241/1 Sudden heating [of leaf juice] inactivates chlorophyllase and so prevents the formation of phaeophorbide. |