## 1 Introduction  
Identification of bioactive peptides has evolved over the years from tedious time-consuming conventional processing steps of purification and characterization into the use of bioinformatic tools to discover the potential precursors of bioactive peptides [1; 2]. The use of protein databases and computer-based tools to assess food protein sequences has become an effective and feasible method to discover and identify the bioactive peptides [2]. The bioinformatics approach combines biological mass data using computer science, biology, mathematics and statistical analysis methods [3]. These in silico approaches include diversified tools as databases of protein and peptide sequences, web-based applications for predicting the bioactivities and physicochemical properties of proteins and peptides, identifying structure-functional relationships of peptide as well as programs that enable the theoretical hydrolysis of proteins. The latter is done by calculating quantitative descriptors and recommending the use of appropriate enzymes as endopeptidase or exoperpeptidases to produce potent peptides from native proteins [4]. Furthermore, use of '-omics' techniques could replace the existing 'trial and error approach' in peptide purification and activity research. The downstream purification process of bioactive peptides can be accelerated by the integration of in silico methods with '-omics' approach. The bioinformatic tools, including universal protein and peptide data bases (UniProtKB, SwissProt, BIOPEP and PepBank), are employed to obtain high throughput related to in silico protein digestion and peptide prediction information on potent bioactive peptide sequences [1; 2]. Therefore, use of bioinformatics is recognized as an effective mining tool to accelerate the process of discovering bioactive peptides encrypted in different types of protein precursors.  
In recent years, much attention has been paid to identifying bioactive peptides originating or produced from seafood processing waste [5; 6; 7]. It is also identified as an effective bio-refinery approach to address the adverse environmental conditions associated with common waste disposal methods [5; 6]. Numerous studies have been conducted for utilizing various marine organisms and their by-products as rich sources of bioactive peptides and essential amino acids [6; 7; 8]. However, when compared to other marine fisheries, sea cucumbers remain a largely untapped marine protein resource [9; 10; 11]. In particular, Atlantic Sea cucumber _Cucumaria fondosa_ is still considered as an emerging fishery in North Atlantic provinces [9; 10]. It is mainly fished for its internal muscle bands and body wall [10; 12]. All the other remaining tissues including aquapharyngeal bulb (flower) and internal organs such as digestive tract, gonads, and respiratory tree are discarded as processing waste [11; 12; 13]. A limited number of studies have reported the potential of utilizing the Atlantic Sea cucumber by-products as precursor materials for bioactive peptides [14; 15]. To the best of our knowledge in silico analysis on hydrolysates prepared from sea cucumber by-products have not been studied to assess their potential as inhibitors of angiotensin converting enzyme (ACE). Furthermore, there are no reports on exploring drug likeliness of sea cucumber derived bioactive peptides.  
For the first time, the present study reports the application of in silico tools to comprehensively study peptidomic data of protein hydrolysates prepared from Atlantic Sea cucumber by-products as sources of antioxidant and ACE inhibitory peptides. In addition, the aim of the study was also to predict the drug likeliness of sea cucumber derived multifunctional peptides.