气相色谱-质谱法测定S-甲基-L-半胱氨酸亚砜(1),S-丙基-L-半胱氨酸亚砜(2)和S-丙烯基-L-半胱氨酸亚砜(3)描述了葱属中的化合物。目标氨基酸被转化为叔丁基二甲基甲硅烷基衍生物。产物在氨基和羧基以及另外的氧原子上被甲硅烷基化,并在非极性毛细管柱上分离。通过质谱法证实已经发生了三个叔丁基二甲基甲硅烷基的掺入,这给出了一个m / z 302片段作为碱基峰(氨基酸侧链消除离子)和m / z 436(1),464(2)或462(3)为主要峰(叔丁基官能团消除了离子),通过电子碰撞电离。在选定的离子监测下,分别在m / z 436(1)和m / z 464(2)下进行的1和2的检出限确定为每次进样0.3 ng和1.8 ng。为了从洋葱的溶剂提取物中(作为代表性的食物原料)洋葱中清除分析物,对样品溶液进行固相萃取。将来自Sep-Pak C(18)柱的洗脱液应用于Bond Elut SCX柱(H(+)形式),然后用0
作者:Elena A. Morozova、Vitalia V. Kulikova、Alexei N. Rodionov、Svetlana V. Revtovich、Natalya V. Anufrieva、Tatyana V. Demidkina
DOI:10.1016/j.biochi.2016.07.007
日期:2016.9
S-substituted l-cysteine sulfoxides is increased by about an order of magnitude compared to the wild type MGL. The antibacterial activity of C115H MGL mixtures with a number of sulfoxides was assessed against Gram-positive and Gram-negative bacteria. The bacteriostatic effect was more pronounced against Gram-positive than against Gram-negative bacteria, while antibacterial potential proved to be quite similar
最近已证明了弗氏柠檬酸蛋氨酸γ-裂合酶(MGL)与新底物L-蛋氨酸和S-(烷基/烯丙基)-1-半胱氨酸亚砜的混合物产生的硫代亚磺酸盐的抗菌活性(Anufrieva et al。,2015 )。这为合理设计新型生物技术相关的抗菌药物生产商开辟了道路。为了增加酶对亚砜的效率,获得了MGL的突变形式,其中用丙氨酸(C115A MGL)和组氨酸(C115H MGL)代替了活性位点半胱氨酸115。组氨酸替代半胱氨酸115会导致突变酶在生理底物的γ消除反应中失去活性,而特征底物的β消除反应则持续存在。然而,与野生型MGL相比,C115H MGL在S取代的L-半胱氨酸亚砜的β-消除反应中的催化效率提高了大约一个数量级。评估了具有多种亚砜的C115H MGL混合物对革兰氏阳性和革兰氏阴性细菌的抗菌活性。对革兰氏阳性菌的抑菌作用比对革兰氏阴性菌的抑菌作用更明显,而抗菌潜力被证明是非常相似的。因此,突变酶C115H
In Vitro Biogeneration of Pure Thiosulfinates and Propanethial-<i>S</i>-oxide
作者:Cunxi Shen、Kirk L. Parkin
DOI:10.1021/jf000711g
日期:2000.12.1
derived from a single ACSO, and a preparation containing a mixture of four thiosulfinate species was derived from reaction mixtures employing binary ACSO substrate systems. Identities of homologous thiosulfinates and PTSO were confirmed by 1H NMR. This approach has the potential to be used as a preparative tool for yielding pure thiosulfinates and PTSO to facilitate the study of chemical and biological properties
开发了一个模型反应系统,使用分离的蒜氨酸酶(EC 4.4.1.4)和分离的或合成的烷基(烯)基-L-半胱氨酸亚砜(ACSO)生成纯硫代亚磺酸盐和丙烷硫氧化物(PTSO)。在21-23摄氏度下3小时后,反应收率范围为30%至60%,并将有机硫反应产物萃取到CHCl3中,以制得具有受控组成的产物制剂。纯的硫代亚磺酸盐或PTSO来源于单一的ACSO,而含有四种硫代亚磺酸盐物质的混合物的制备则来自采用二元ACSO底物系统的反应混合物。同源硫代亚磺酸盐和PTSO的身份通过1 H NMR确认。
[EN] IMPROVEMENTS IN OR RELATING TO ALLIUM EXTRACTS<br/>[FR] PERFECTIONNEMENTS APPORTÉS OU SE RAPPORTANT À DES EXTRAITS D'ALLIUM
申请人:LEPTREX LTD
公开号:WO2015008019A1
公开(公告)日:2015-01-22
The present invention relates to improvements in or relating to Allium extracts. In particular, it relates to improvements in or relating to extending the therapeutic half- life or duration of Allium extracts. The invention also relates to the synthesis of certain thiosulfinate compounds, especially to the synthesis of methyl allyl thiosulfinate and allyl methyl thiosulfinate, in particular from either methiin or alliin alone or a mixture of both. The invention further relates to the synthesis of methyl allyl thiosulfinate, allyl methyl thiosulfinate, allicin, and methyl methyl thiosulfinate in a mixture with varying molar or mass ratios depending on the reaction conditions, in particular from either methiin or alliin alone or a mixture of both. A high yielding, optimized synthesis of allicin starts from alliin, whereas methyl methyl thiosulfinate is advantageously obtained from methiin. Also provided is a kit comprising methiin in a first container and/or alliin in a second container and an allinase source, in particular garlic powder in a third container. Finally, the invention provides a method of preparing a mixture of methyl allyl thiosulfinate, allyl methyl thiosulfinate, allyl allyl thiosulfinate (allicin) and methyl methyl thiosulfinate from methiin and pieces of an Allium species.
Asymmetric synthesis of (<i>S,R</i>)- and (<i>R,R</i>)-methiin stereoisomers
作者:Anastasy О. Kolodiazhna、Аleksei I. Skliarov、Alena A. Slastennikova、Oleg I. Kolodiazhnyi
DOI:10.1080/10426507.2020.1755972
日期:2020.9.1
Abstract An asymmetric synthesis of (+)- and (–)-methiine (S-methyl-(R)-cysteine sulfoxide) diastereomers has been developed. These natural sulfur compounds were isolated from a variety of Brassica vegetables. As the starting compound, (R)-cysteine was used, which was methylated to form (R)-S-methylcysteine. Then the oxidation of S-methylcysteine with tert-butyl hydroperoxide catalyzed by the chiral