Fish skin gelatin-based emulsion as a delivery system to protect lipophilic bioactive compounds during in vitro and in vivo digestion: The case of benzyl isothiocyanate

Construction of benzyl isothiocyanate-loaded fish skin gelatin-luteolin compound emulsion delivery system, and its digestion and absorption characteristics

BACKGROUND

Fish skin gelatin (FSG) and luteolin (LUT) were used as composite emulsifiers, and benzyl isothiocyanate (BITC) was used as a model of nutrient delivery to construct a stable emulsion. The storage stability of the FSG-LUT emulsion and its effect on BITC release were investigated both in vitro and ex vivo.

RESULTS

LUT can quench FSG fluorophores statically and form a stable complex through hydrogen bonding and hydrophobic interactions. The FSG-LUT emulsion storage stability and embedding rate were higher than those of the FSG emulsion. The FSG-LUT emulsion microstructure was resistant to oral and gastric digestion, and the BITC retention rate and bioaccessibility were much higher than those of the FSG emulsion. Lastly, the ex vivo everted gut sac of rat intestine study demonstrated that BITC showed the highest absorption in the ileum, and the FSG-LUT emulsion absorbed BITC and sustained a controlled release in a specific position.

CONCLUSION

LUT could form stable complexes with FSG, which improved the stability and bioavailability of BITC in the FSG-LUT emulsion delivery system, and promoted further intestinal BITC absorption. © 2022 Society of Chemical Industry.

In Vitro-In Vivo Study of the Impact of Excipient Emulsions on the Bioavailability and Antioxidant Activity of Flavonoids: Influence of the Carrier Oil Type

The influence of the carrier oil type on the bioavailability and bioactivity of flavonoids (quercetin, kaempferol, and apigenin) was examined using in vitro digestion, in situ intestinal perfusion, and pharmacokinetic studies. Here, medium-chain triglycerides (MCTs), long-chain triglycerides (LCTs), or MCT/LCT mixtures (1:1, w/w) served as the oil phase of excipient emulsions. Overall, the bioavailability and antioxidant activity of flavonoids increased when they were coingested with excipient emulsions. The in vitro bioaccessibility of flavonoids was affected by the carrier oil: LCT (17.9-22.8%) > MCT/LCT (12.1-13.7%) > MCT (9.2-12.6%). These differences were mainly attributed to the fact that the mixed micelles formed after the digestion of LCTs had larger hydrophobic domains to solubilize more flavonoids. However, in vivo pharmacokinetic experiments showed that the flavonoid concentrations in rat serum were comparable for all carrier oils (p > 0.05). Our results assist in formulating excipient emulsions to enhance the efficacy of flavonoids.

Influence of fish skin gelatin-sodium alginate complex stabilized emulsion on benzyl isothiocyanate stability and digestibility in vitro and in vivo

BACKGROUND

An emulsion delivery system for benzyl isothiocyanate (BITC) was prepared using fish skin gelatin (FSG) and sodium alginate (Alg). The effects of the FSG-Alg complex on the emulsion stability and BITC release pattern from the emulsion were investigated in vitro and in vivo.

RESULTS

The storage stability and embedding rate of the 10 g kg^-1 FSG and 2.5 g kg^-1 Alg (FSG-Alg) emulsion were the highest among all samples. The FSG-Alg complex provided BITC a better protection during in vitro digestion. The microstructure of the FSG-Alg emulsions was more stable during in vitro digestion, and the bioaccessibility and retention rate of BITC were much higher compared to those of the FSG emulsion. The results of the ex vivo everted gut sac of rat intestine study showed that the FSG-Alg emulsion significantly increased the BITC absorption rate in the duodenum.

CONCLUSION

The FSG-Alg emulsion delivery system is a highly stable system for the delivery of BITC that improves the bioaccessibility of BITC and promotes its absorption in the duodenum. © 2022 Society of Chemical Industry.

Current Research on the Extraction, Functional Properties, Interaction with Polyphenols, and Application Evaluation in Delivery Systems of Aquatic-Based Proteins

Globally, aquatic processing industries pay great attention to the production of aquatic proteins for the fulfillment of the nutritive requirements of human beings. Aquatic protein can replace terrestrial animal protein due to its high protein content, complete amino acids, unique flavor, high quality and nutritional value, and requirements of religious preferences. Due to the superior functional properties, an aquatic protein based delivery system has been proposed as a novel candidate for improving the absorption and bioavailability of bioactive substances, which might have potential applications in the food industry. This review outlines the extraction techniques for and functional properties of aquatic proteins, summarizes the potential modification technologies for interaction with polyphenols, and focuses on the application of aquatic-derived protein in delivery systems as well as their interaction with the gastrointestinal tract (GIT). The extraction techniques for aquatic proteins include water, salt, alkali/acid, enzyme, organic solvent, and ultrasound-assisted extraction. The quality and functionality of the aquatic proteins could be improved after modification with polyphenols via covalent or noncovalent interactions. Furthermore, some aquatic protein based delivery systems, such as emulsions, gels, films, and microcapsules, have been reported to enhance the absorption and bioavailability of bioactive substances by in vitro GIT, cell, and in vivo animal models. By promoting comprehensive understanding, this review is expected to provide a real-time reference for developing functional foods and potential food delivery systems based on aquatic-derived proteins.