Merck silica gel 60 pf254 366

All the reagents and chemicals used for extraction, column chromatography (CC), thin layer chromatography (TLC), gas chromatography–mass spectrometry (GC–MS), NMR and chemical synthesis were HPLC grade (such as Fmoc-Pro-OH, Fmoc-Leu-OH, HOBt, EDC, DMF, DIPEA, DCM, piperidine, LiOH and MeOH), and were purchased from sigma Aldrich and Millipore. Column chromatography was carried out on silica gel 60 (0.040–0.063 mm, Merck, Darmstadt, Germany). TLC was performed with pre-coated Merck silica gel 60 _PF254+366 (Merck, Darmstadt, Germany). Tryptic soy Broth (TSB) was purchased from Biolife.

NMR spectra (¹H NMR, ¹³C NMR, DEPT, COSY, HMQC, and HMBC) were measured on Bruker Avance DRX 500 spectrometer using standard pulse sequences and referenced to residual solvent signals. Column chromatography was carried out on silica gel 60 (0.040–0.063 mm, Merck, Darmstadt, Germany) and Sephadex LH-20 (GE Healthcare, Uppsala, Sweden) as stationary phases. ESI-MS was done on a Micromass AC-TOF micro mass spectrometer (Micromass, Agilent Technologies 1200 series, Tokyo, Japan). Analytical TLC was performed with pre-coated Merck silica gel 60 _PF254+366 (Merck, Darmstadt, Germany). R_f values of the strain extract bioactive compounds and visualization of their chromatograms was carried out with UV light (254 and 366 nm) followed by spraying with anisaldehyde-sulfuric acid and heating. Acetylcholine iodide, AChE from electric eel (type VI-S lyophilized powder), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2’ azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid (ABTS⁺), 5,5-dithiobis-2-nitrobenzoic acid (DTNB), BHA (butylated hydroxyanisole) and BHT (butylated hydroxytoluene), galanthamine were obtained from Sigma-Aldrich (Germany).