Ultrasound-mediated fucoxanthin rich oil nanoemulsions stabilized by κ-carrageenan: Process optimization, bio-accessibility and cytotoxicity.

This work aims to produce and optimize a κ-carrageenan-based nanoemulsion (NE) to encapsulate seaweed oil, which is rich in fucoxanthin (FX), using ultrasound-assisted emulsification. κ-Carrageenan was produced using subcritical water, and seaweed oil was extracted using supercritical carbon dioxide with sunflower oil as the co-solvent. Response surface methodology (RSM) was used to understand the influence of several process parameters such as ultrasound amplitude, time, temperature, and duty cycle to produce an NE. The RSM factor was used to focus on droplet size, polydispersity index, zeta potential, viscosity, antioxidant, FX, encapsulation efficiency, and emulsion stability. Our outcomes suggested that the ultrasound process had a noteworthy influence on the NE. The best conditions to obtain an NE were an ultrasound amplitude of 87 µm, a sonication time of 394 s, a temperature of 60 °C, and a duty cycle of 50%. The resulting NE was studied by UV-Vis, Fourier-transform infrared spectroscopy, thermal gravimetric analysis, differential scanning calorimetry, scanning electron microscopy, atomic force microscopy, and X-ray diffraction. Moreover, the NE obtained from optimized conditions was checked for fatty acid content, color, oxidative stability, in vitro digestion, bioaccessibility of FX, and cytotoxicity. The results obtained suggest that lower droplet size of the emulsion can improve oxidative stability, in vitro digestion, bioaccessibility of FX, and good cell inhibition against a few cell lines. Therefore, a κ-carrageenan-stabilized NE can be used as a potential delivery system to endorse applications of seaweed oil, which is rich in FX, in functional foods, beverage systems, and pharmaceuticals.

Optimization of polysaccharides extraction from Pacific oyster (Crassostrea gigas) using subcritical water: Structural characterization and biological activities.

Bioactive polysaccharide was extracted from Pacific oyster Crassostrea gigas using subcritical water (SW) and the extraction process was optimize by response surface methodology (RSM). The optimum condition was found to be temperature 125.01 °C, extraction time 14.93 min, and liquid to solid ratio of 44.69:1 (ml:g). At this condition, the yield of the C. gigas polysaccharides (CGPs) was found to be 18.66%. The polysaccharide was characterized for its chemical, physical, thermal, and structural properties using HPLC, GPC, XRD, FTIR, TGA, UV-Vis spectroscopy, and NMR and the results of this characterization showed a characteristic feature of a typical polysaccharide. The CGPs was found to be a d-glucan with α-(1 → 4) configuration. The CGPs was also evaluated for its antioxidant, antihypertensive, and hypoglycemic activity and the IC50 (mg/ml) values were found to be 2.06 ±â€¯0.33, 1.58 ±â€¯0.03, and 2.77 ±â€¯0.01 respectively. The current study demonstrated that SWE could be used as an effective process to extract bioactive polysaccharides from C. gigas.

Deep eutectic solvent-based extraction and fabrication of chitin films from crustacean waste.

In this study, chitin was exclusively extracted from shrimp shells (Marsupenaeus japonicas) through a green solvent called deep eutectic solvent (DES), and various types of DES were utilized to extract chitin. The physicochemical properties of the obtained chitin were compared with the conventional method. A high purity of chitin was obtained while using DES-8 (choline chloride-malonic acid) with a yield of 19.41% ±â€¯1.35%, and purity was confirmed using 13C nuclear magnetic resonance. The DES-produced chitin was utilized to produce chitin films and was compared with standard chitin films. The obtained films were characterized by SEM, AFM, TGA, DSC, FTIR, mechanical properties, moisture sorption, swelling behavior, and biodegradation. The DES film showed similar properties to the standard film, while the mechanical properties, swelling behavior, and biodegradation of the DES chitin films proved to be similar to standard chitin film. These chitin films can be used as wound healing resources.