Friedman M, Grosjean O K, Zahnley J C
Food Chem Toxicol. 1986 Sep;24(9):897-902. doi: 10.1016/0278-6915(86)90316-9.
Phenylethylaminoalanine (PEAA), derived from biogenic phenylethylamine and dehydroalanine, inhibited the enzymatic activity of the metalloenzyme, carboxypeptidase A (CPA). The inhibition was maximal at pH 7.0 in the pH range 7-8.5. The extent of inhibition increased with time of treatment and PEAA concentration. N-AcetylPEAA did not inhibit the enzyme, suggesting that the free alpha-NH2 group is required for inhibition. PEAA also inactivated the copper enzyme, polyphenol oxidase (tyrosinase). Comparative studies with three other inhibitors, lysinoalanine, ethylenediaminetetraacetic acid and sodium phytate, suggest that the potency of PEAA as an inhibitor of CPA is similar to that of sodium phytate. Of these four inhibitors and three thiol compounds also tested, PEAA was the least and cysteine the most effective against tyrosinase. The pattern of observations in these studies suggests differences in the mechanisms of action of the inhibitors studied. The formation of PEAA, lysinoalanine and sodium phytate in foods is of possible nutritional and toxicological significance.
苯乙氨基丙氨酸（PEAA）由生物源苯乙胺和脱氢丙氨酸衍生而来，它抑制金属酶羧肽酶A（CPA）的酶活性。在pH 7 - 8.5范围内，pH 7.0时抑制作用最大。抑制程度随处理时间和PEAA浓度的增加而增大。N - 乙酰PEAA不抑制该酶，这表明抑制作用需要游离的α - NH₂基团。PEAA还能使铜酶多酚氧化酶（酪氨酸酶）失活。与其他三种抑制剂（赖氨酸丙氨酸、乙二胺四乙酸和植酸钠）的比较研究表明，PEAA作为CPA抑制剂的效力与植酸钠相似。在这四种抑制剂以及同样测试的三种硫醇化合物中，PEAA对酪氨酸酶的抑制作用最小，半胱氨酸最有效。这些研究中的观察结果模式表明所研究的抑制剂作用机制存在差异。食物中PEAA、赖氨酸丙氨酸和植酸钠的形成可能具有营养和毒理学意义。
