Cortez-Espinosa Nancy, Aviña-Verduzco Judit A, Ramírez-Chávez Enrique, Molina-Torres Jorge, Ríos-Chávez Patricia
Escuela de Biología, Universidad Michoacana de San Nicolas de Hidalgo, Cd. Universitaria, C.P 58030. Morelia, Michoacán, México.
Nat Prod Commun. 2011 Jun;6(6):857-61.
Acmella radicans (Asteraceae) produces at least seven alkamides, most with either an isobutyl- or phenylethyl group as the amine moiety. These moieties suggest that the amino acids valine and phenylalanine are the biosynthetic precursors of these alkamides. On the basis of labeled feeding experiments using either L-[2H8]valine or L-[2H8]phenylalanine we present evidence for the involvement of these two amino acids in the biosynthesis of (2E,6Z,8E)-N-isobutyl-2,6,8-decatrienamide (affinin) (1), (2Z,4E)-N-(2-phenylethyl)-2,4-octadienamide (2), (2E)-N-(2-phenylethyl)-nona-2-en-6,8-diynamide (3), and 3-phenyl-N-(2-phenylethyl)-2-propenamide (4). Alkamides were isolated from young A. radicans plants and analyzed by gas chromatography-mass spectrometry (GC-MS). Additionally, in cell free in vitro experiments based on isobutyl and phenylethylamide biosynthesis, using a colorimetric assay and GC-MS, valine and phenylalanine decarboxylase activities were assayed in the soluble extract of A. radicans leaves.
放射金钮扣（菊科）至少产生七种酰胺生物碱，其中大多数的胺部分为异丁基或苯乙基。这些部分表明缬氨酸和苯丙氨酸是这些酰胺生物碱的生物合成前体。基于使用L-[2H8]缬氨酸或L-[2H8]苯丙氨酸的标记饲喂实验，我们提供了证据，证明这两种氨基酸参与了（2E,6Z,8E）-N-异丁基-2,6,8-癸三烯酰胺（阿非宁）（1）、（2Z,4E）-N-（2-苯乙基）-2,4-辛二烯酰胺（2）、（2E）-N-（2-苯乙基）-壬-2-烯-6,8-二炔酰胺（3）和3-苯基-N-（2-苯乙基）-2-丙烯酰胺（4）的生物合成。从放射金钮扣的幼株中分离出酰胺生物碱，并通过气相色谱-质谱联用仪（GC-MS）进行分析。此外，在基于异丁基和苯乙酰胺生物合成的无细胞体外实验中，使用比色测定法和GC-MS，对放射金钮扣叶片的可溶性提取物中的缬氨酸和苯丙氨酸脱羧酶活性进行了测定。
