Comprehensive Extraction of Shrimp Head Lipids and Peptides from Litopenaeus vannamei: Evaluation of Neuroprotective Potential and Constituent Analysis

The increasing prevalence of Alzheimer’s disease has created a substantial and urgent need for brain-healthy functional foods. The processing of Pacific white shrimp (Litopenaeus vannamei) generates considerable amounts of head waste, which is rich in bioactive compounds, including lipids and peptides, holding great promise for the development of nutraceuticals to support human brain health. However, traditional extraction methods are time-consuming and inefficient in fully utilizing these compounds. This study aimed to explore the functional properties of these shrimp head-derived ingredients using “one-step” three-phase partitioning (TPP) followed by successive proteolysis. The extracted polar lipid (PL-SH), protein (P-SH) and proteolytic peptidic product (Pep-SH) from shrimp heads were screened for their antioxidant, neuroprotective, and anti-neuroinflammatory activities. Antioxidant activities were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+), and hydroxyl free radical scavenging assays, all of which revealed strong antioxidant potential for all three products. Neuroprotective activities were assessed using HT-22 mouse hippocampal neuronal cells challenged with Aβ25−35, and anti-neuroinflammatory activities were evaluated using BV-2 microglial cells stimulated with lipopolysaccharide (LPS). The results suggested that both PL-SH and Pep-SH exerted protective effects against Aβ25−35-induced cell damage under the tested conditions, and PL-SH also reduced nitric oxide (NO) production induced by LPS, indicating potential anti-neuroinflammatory activity. However, further studies with additional biomarkers (e.g., ROS, apoptosis markers, and cytokines) are required to confirm these effects. The lipid composition of PL-SH was further characterized by thin-layer chromatography and LC-MS/MS-based lipidomics, revealing various classes of phospholipids. Furthermore, analysis of the molecular weight distribution and sequences of peptides in Pep-SH revealed peptide sizes ranging from 70 to 1700 Da and a high degree of homology to known antioxidant and neuroprotective peptide sequences. These findings suggest that lipids and peptides from Pacific white shrimp heads possess valuable functional properties, supporting their potential use in the development of functional foods for neuroprotection and anti-neuroinflammation.