Harnessing Thalassochemicals: Marine Saponins as Bioactive Agents in Nutraceuticals and Food Technologies

Abstract

The expanding field of nutraceuticals and functional food science is increasingly turning to marine-derived bioactive compounds, particularly saponins, for their diverse pharmacological properties. These so-called thalassochemicals display distinctive structural features-such as sulfated glycosidic moieties and amphiphilic backbones-that underpin potent antitumor, hypolipidemic, antioxidant, and antimicrobial activities. In contrast to their terrestrial analogs, marine saponins remain underexplored, and their complexity poses analytical and functional challenges. This review provides a critical and integrative synthesis of recent advances in the structural elucidation, biological function, and technological application of marine saponins. Special emphasis is placed on the unresolved limitations in their isolation, characterization, and structural validation, including coelution of isomers, adduct formation in MS spectra, and lack of orthogonal techniques such as NMR or FTIR. We illustrate these limitations through original MS/MS data and propose experimental workflows to improve compound purity and identification fidelity. In addition to discussing known structure-activity relationships (SARs) and mechanisms of action, we extend the scope by integrating recent developments in computational modeling, including machine learning, molecular descriptors, and quantitative structure-activity relationship (QSAR) models. These tools offer new avenues for predicting saponin bioactivity, despite current limitations in available high-quality datasets. Furthermore, we include a classification and comparison of steroidal and triterpenoid saponins from marine versus terrestrial sources, complemented by detailed chemical schematics. We also address the impact of processing techniques, delivery systems, and bioavailability enhancements using encapsulation and nanocarriers. Finally, this review contextualizes these findings within the regulatory and sustainability frameworks that shape the future of saponin commercialization. By bridging analytical chemistry, computational biology, and food technology, this work establishes a roadmap for the targeted development of marine saponins as next-generation nutraceuticals and functional food ingredients.

Keywords: bioactive compounds; food technology; marine biomaterials; nutraceuticals; saponins; thalassochemicals.

Figure 1

Extraction techniques for saponins, comparing conventional and advanced methods, including supercritical fluid extraction, ultrasonic-assisted extraction, and microwave-assisted extraction.

Figure 2

Representative MS and MS/MS spectra from Cucumaria frondosa extracts. (a–c) Q1 and MS/MS at 20 and 40 eV of a presumed saponin showing a clear glycone–aglycone fragmentation pattern; (d–f) signal showing formation of a [M+H+Na]²⁺ adduct and irregular fragmentation; (g–i) complex signal group lacking clear fragmentation behavior. These patterns highlight the challenges in compound purity and structural resolution using mass spectrometry alone.

Figure 3

Encapsulation strategies to enhance the stability and bioavailability of saponins, including nanoemulsions, liposomes, and polymeric nanoparticles.

Figure 4

Structural classification of saponins, highlighting key differences between triterpenoid, steroidal, and marine-derived saponins.

Figure 5

Biosynthetic pathways of saponins in terrestrial and marine organisms, illustrating enzymatic modifications that contribute to their bioactivity.

Figure 6

Graphical analysis of molecular descriptors in a curated dataset of saponins, including both terrestrial and marine structures. (A) Rotatable bonds vs. number of heavy atoms, (B) molecular weight vs. complexity, (C) TPSA vs. number of rings, (D) molecular weight vs. defined stereocenters, (E) rotatable bonds vs. number of rings, and (F) TPSA vs. rotatable bonds.

Figure 7

Graphical analysis of molecular descriptors restricted to marine saponins. The same structural trends are observed as in Figure 6, although the lower number of data points results in less pronounced trends.

Figure 8

Saponin structures and their bioactivities, illustrating interactions with cellular components and major therapeutic targets.

Figure 9

Industrial applications of saponins in pharmaceuticals, functional foods, and cosmetics, emphasizing their role as emulsifiers, adjuvants, and bioactive agents.

Figure 10

Nanotechnology-based delivery systems for saponins, including nanoemulsions, liposomes, and polymeric nanoparticles, which enhance bioavailability and controlled release.

Figure 11

Proposed future directions for marine saponin research, emphasizing sustainability, regulatory challenges, and potential applications in next-generation nutraceuticals.