Natural Product Communications ( IF 1.8 ) Pub Date : 2020-09-23 , DOI: 10.1177/1934578x20961186 YanHua Tian 1, 2 , HuiZhi Du 1 , Li Wang 1 , ShiFei Li 1 , Lu Zhang 1 , LiWei Zhang 1
Diospyros lotus L. leaves are used as a functional tea and folk medicine in several Asian countries. This study aimed to evaluate the effects of phenolic extracts of the leaves on scavenging nitrite and inhibiting N-nitrosamines (NAs) formation and to determine the active ingredients responsible for these effects. Of the 7 fractions (Fr1-Fr7) prepared from the extract of D. lotus leaves, Fr5 contained the highest phenolic content and exhibited the strongest activity. Five active ingredients of Fr5 were discovered, and 4 of them were identified as myricitrin (Mytr), myricetin (Myt), myricetin-3-O-β-d-glucoside (Myt-Glc), and myricetin-3-O-β-d-galactoside (Myt-Gal). The content of Mytr was much higher than those of the other 3 ingredients, both in Fr5 and extracts of D. lotus leaves. Finally, Mytr and Myt were proved to have stronger activities by the 1,1-diphenyl-2-trinitrophenyl hydrazine scavenging, nitrite scavenging, and inhibition of NAs formation assays. These results indicated that Mytr was the main active ingredient of D. lotus leaves. Myt, Mytr, and Fr5 from the leaves could be used as natural agents for antioxidant, nitrite scavenging, and inhibition of NAs formation in food and the human body.
中文翻译:
亚硝酸盐清除和抑制Ñ -Nitrosamines形成由酚醛提取物从黑枣L.叶和活性成分
柿属的荷叶柿在许多亚洲国家被用作功能性茶和民间药。这项研究旨在评估叶子的酚类提取物对清除亚硝酸盐和抑制N-亚硝胺(NAs)形成的作用,并确定引起这些作用的活性成分。由荷叶D提取物制备的7个馏分(Fr 1 -Fr 7)中,Fr 5的酚含量最高,活性最强。发现了5种Fr 5的活性成分,其中4种被鉴定为杨梅素(Mytr),杨梅素(Myt),杨梅素3- O-β - d-葡萄糖苷(Myt-Glc)和杨梅素-3- O-β - d-半乳糖苷(Myt-Gal)。Myr的含量远高于其他3种成分,无论是在Fr 5还是D.荷叶提取物中。最后,通过1,1-二苯基-2-三硝基苯基肼清除,亚硝酸盐清除和抑制NAs形成实验证明Mytr和Myt具有更强的活性。这些结果表明,Mytr是D.荷叶的主要活性成分。叶子的Myt,Mytr和Fr 5可用作天然抗氧化剂,亚硝酸盐清除剂,并抑制食物和人体中NAs的形成。