School of Computing, Engineering, & Physical Sciences, University of the West of Scotland, Paisley PA1 2BE, UK.
National Institute of Fundamental Studies, Hantana Road, Kandy 20000, Sri Lanka.
Mar Drugs. 2021 Apr 20;19(4):232. doi: 10.3390/md19040232.
Epicotripeptin (), a new cyclic tripeptide along with four known cyclic dipeptides (-) and one acetamide derivative () were isolated from seagrass-associated endophytic fungus M13 recovered from the Red Sea. Additionally, two new compounds, cyclodidepsipeptide phragamide A () and trioxobutanamide derivative phragamide B (), together with eight known compounds (-), were isolated from plant-derived endophyte 13A collected from a saline lake of Wadi El Natrun depression in the Sahara Desert. The structures of the isolated compounds were determined based on the 1D and 2D NMR spectroscopic data, HRESIMS data, and a comparison with the reported literature. The absolute configurations of and were established by advanced Marfey's and Mosher's ester analyses. The antimicrobial screening indicated that seven of the tested compounds exhibited considerable (MIC range of 2.5-5 µg/mL) to moderate (10-20 µg/mL) antibacterial effect against the tested Gram-positive strains and moderate to weak (10-30 µg/mL) antibacterial effect against Gram-negative strains. Most of the compounds exhibited weak or no activity against the tested Gram-negative strains. On the other hand, four of the tested compounds showed considerable antibiofilm effects against biofilm forming Gram-positive and Gram-negative strains.
从红海来源的海草内生真菌 M13 中分离出了一种新的环三肽，以及四种已知的环二肽 (-) 和一种乙酰胺衍生物 ()。此外，从撒哈拉沙漠 Wadi El Natrun 洼地的盐湖中分离到植物内生菌 13A 中，分离出了两种新化合物，环二肽 Phragamide A ()和三氧代丁酰胺衍生物 Phragamide B ()，以及八种已知化合物 (-)。根据 1D 和 2D NMR 波谱数据、HRESIMS 数据以及与文献报道的比较，确定了分离化合物的结构。通过先进的 Marfey's 和 Mosher's 酯分析确定了 和 的绝对构型。抗菌筛选表明，在所测试的化合物中，有七种对测试的革兰氏阳性菌株具有相当大的（MIC 范围为 2.5-5 µg/mL）至中等（10-20 µg/mL）的抗菌作用，对革兰氏阴性菌株具有中等至弱（10-30 µg/mL）的抗菌作用。大多数化合物对测试的革兰氏阴性菌株表现出弱或无活性。另一方面，在所测试的形成生物膜的革兰氏阳性和革兰氏阴性菌株中，有四种化合物表现出相当大的抗生物膜作用。
