Investigating novel bioactive peptides from ginger rhizome: in silico and in vitro approaches

<p dir="ltr">Ginger rhizome, i.e., <i>Zingiber officinale</i> Roscoe (Zingiberaceae) is widely utilised in Tibb-Unani, Chinese, and Ayurvedic herbal medicine systems to treat a wide array of unrelated ailments. Despite its extensive use, there is a lack of studies comprehensively characterising the ginger rhizome proteome (~2% of rhizome mass) for its functional benefits. The aim of this study was to identify bioactive peptides from ginger rhizome using both computational and experimental methods, to establish a link to its functional properties. The total protein extracted from the rhizome was hydrolysed under five different enzymatic conditions to generate a diverse range of unique peptides. LC-MS/MS analysis identified 481 unique peptides, with 41 predicted to be bioactive by PeptideRanker and BIOPEP. Additionally, bioinformatic tools including AnOxPePred, AHTPin, ClassAMP, and ToxinPred were employed to screen peptides for antioxidant, antihypertensive, and antibacterial activities, while the accuracy of predictions for the 4 high scoring bioactive peptide candidates was validated by in vitro methods. Molecular docking simulations provided mechanistic insights into the tested peptides. Notably, P3 (GPEKIFYDGPYL) exhibited significant antioxidant activity, followed by P2 (FASYPVKK) and P1 (GSPVWIIPEPT), while P4 (IAISPSYPIK) was observed to be a potent mixed-type ACE-inhibitor and a bacteriostatic agent. The study also observed discrepancies in prediction results among bioinformatic computational tools, underscoring the importance of complementing these tools with in vitro and in vivo methods for better research outcomes.</p>