Synthesis and Characterization of Short α and β-Mixed Peptides with Excellent Anti-Lipase Activities

Abstract

Obesity is a source of significant pathologies and deadly diseases, including heart disease, diabetes, and cancer. One of the most intriguing strategies in the hunt for new anti-obesity medications is the inhibition of pancreatic lipase (PL). This study presents a novel application of short α and β-mixed peptides as pancreatic lipase inhibitors. These peptides were synthesized in the solution phase and characterized using FTIR and 1H-NMR. L-proline is present in a high percentage of natural anti-lipase peptides and was used as a β-amino acid in this study to enhance anti-lipase activity and proteolytic stability. Moreover, L-α-proline was converted to β-amino acid derivatives using the Arndt–Eistert method with the advantage of stereo control at the α-carbon. The synthesized peptides with anti-lipase activity are N-Boc-β-Pro-Gly-OBz (93%), N-Boc-O-Bz-Tyr-β-Pro-β-Pro-Gly-OBz (92%), N-Boc-O-Bz-Tyr-β-Pro-COOH (91%), N-Boc-Phe-β-Pro-OCH3 (90%), and N-Boc-O-Bz-Tyr-β-Pro-OCH3 (89%). These peptides may function as lead molecules for further modification to more significant molecules, which can help control obesity.

Distribution and Level of Bioactive Monoacylglycerols in 12 Marine Microalgal Species

“…The mixture was left to react overnight at 45 • C. The reaction mixture was then diluted with MilliQ water, and the basic solution neutralised with hydrochloric acid (HCl) 6 M. The aqueous reaction mixture was subsequently extracted twice with diethyl ether; the organic phase was transferred into pre-weighed vials and dried under N 2 stream and under vacuum to remove solvent traces. Free FAs were converted into their corresponding methyl esters (FAME) by adding an excess (1 mL) of an ethereal solution of diazomethane (CH 2 N 2 ) freshly prepared in-house from Diazald ® (Merck, Milan, Italy) using a commercial glass kit purchased by Merck [53]. After a reaction time of 60 min, samples were dried under N 2 stream and stored at −20 • C. For GC-MS analysis, the samples were dissolved in dichloromethane (300 µL) and transferred into autosampler vials.…”