Microalgae are unicellular marine organisms that have promoted complex biochemical pathways to survive in greatly competitive marine environments. They could contain significant amounts of high-quality proteins which, because of their structural diversity, contain a range of yet undiscovered novel bioactive peptides. In this work, a peptidomic platform was developed for the separation and identification of bioactive peptides in protein hydrolysates. In this work, a peptidomic platform was developed for the extraction, separation, and identification of bioactive peptides in protein hydrolysates. Indeed, extraction of proteins from recalcitrant tissues is still a challenge due to their strong cell walls and high levels of non-protein interfering compounds. Therefore, seven different protein extraction protocols, based on mechanical and chemical methods, were tested in order to produce high-quality protein extracts. Proteins obtained by means of the best protocol, consisting of milling the recalcitrant tissue with glass beads, were subjected to enzymatic digestion with Alcalase® and subsequently the hydrolysate was purified by two-dimensional semi-preparative reversed phase liquid chromatography. Fractions were assayed for antioxidant and antihypertensive activities and only the most active ones were finally analyzed by RP nanoHPLC-MS/MS. Around 500 peptide sequences were identified in these fractions. The identified peptides were subjected to an in silico analysis by PeptideRanker algorithm in order to assign a score of bioactivity probability. Twenty-five sequenced peptides were found with potential antioxidant and angiotensin-converting-enzyme-inhibitory activities. Four of these peptides, WPRGYFL, GPDRPKFLGPF, WYGPDRPKFL, SDWDRF, were selected for synthesis and in vitro tested for specific bioactivity, exhibiting good values of antioxidant and ACE-inhibitory activity.

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微藻是单细胞海洋生物，已促进复杂的生化途径在激烈竞争的海洋环境中生存。它们可能包含大量的高质量蛋白质，由于它们的结构多样性，它们包含一系列尚未发现的新型生物活性肽。在这项工作中，开发了一种肽学平台，用于分离和鉴定蛋白质水解物中的生物活性肽。在这项工作中，为提取，分离和鉴定蛋白水解物中的生物活性肽开发了一种肽组学平台。实际上，由于顽强的组织细胞壁和高水平的非蛋白质干扰化合物，从顽calc的组织中提取蛋白质仍然是一个挑战。因此，有七种不同的蛋白质提取方案，以机械和化学方法为基础，进行了测试，以生产高质量的蛋白质提取物。将通过最佳方案获得的蛋白质（包括用玻璃珠研磨顽固的组织）进行酶消化，然后通过二维半制备型反相液相色谱法纯化水解产物。测定级分的抗氧化和抗高血压活性，最后仅通过RP nanoHPLC-MS / MS分析最活跃的级分。在这些馏分中鉴定出约500个肽序列。通过PeptideRanker算法对鉴定出的肽进行计算机分析，以分配生物活性概率分数。发现二十五个测序的肽具有潜在的抗氧化剂和血管紧张素转化酶抑制活性。选择了其中的四种肽WPRGYFL，GPDRPKFLGPF，WYGPDRPKFL，SDWDRF进行合成，并在体外测试了特定的生物活性，表现出良好的抗氧化剂和ACE抑制活性值。

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