Effects of sonication and ultrasound on properties and bioactivities of liposomes loaded with hydrolyzed collagen from defatted sea bass skin conjugated with epigallocatechin gallate

Review of fish protein hydrolysates: production methods, antioxidant and antimicrobial activity and nanoencapsulation

Marine products have gained popularity due to their valuable components, especially protein, despite generating significant waste. Protein hydrolysates are widely recognized as the most effective method for transforming these low-value raw materials into high-value products. Fish protein hydrolysate (FPH), sourced from various aquatic wastes such as bones, scales, skin, and others, is rich in protein for value-added products. However, the hydrophobic peptides have limitations like an unpleasant taste and high solubility. Microencapsulation techniques provide a scientific approach to address these limitations and safeguard bioactive peptides. This review examines current research on FPH production methods and their antioxidant and antibacterial activities. Enzymatic hydrolysis using commercial enzymes is identified as the optimal method, and the antioxidant and antibacterial properties of FPH are substantiated. Microencapsulation using nanoliposomes effectively extends the inhibitory activity and enhances antioxidant and antibacterial capacities. Nevertheless, more research is needed to mitigate the bitter taste associated with FPH and enhance sensory attributes.

Ultrasonic-assisted extraction of grape seed procyanidins, preparation of liposomes, and evaluation of their antioxidant capacity

The residue remaining after oil extraction from grape seed contain abundant procyanidins. An ultrasonic-assisted enzyme method was performed to achieve a high extraction efficiency of procyanidins when the optimal extraction conditions were 8 U/g of cellulase, ultrasound power of 200 W, ultrasonic temperature of 50 ℃, and ultrasonic reaction time of 40 min. The effects of free procyanidins on both radical scavenging activity and thermal stability at 40, 60, and 80 ℃ of the procyanidins-loaded liposomal systems prepared by the ultrasonic-assisted method were discussed. The presence of procyanidins at concentrations ranging from 0.02 to 0.10 mg/mL was observed to be effective at inhibiting lipid oxidation by 15.15 % to 69.70 % in a linoleic acid model system during reaction for 168 h, as measured using the ferric thiocyanate method. The procyanidins-loaded liposomal systems prepared by the ultrasonic-assisted method were characterized by measuring the mean particle size and encapsulation efficiency. Moreover, the holographic plots showed that the effect-response points of procyanidins combined with α-tocopherol in liposomes were lower than the addition line and 95 % confidence interval limits. At the same time, there were significant differences between the theoretical IC50add value and the experimental IC50mix value. The interaction index (γ) of all combinations was observed to be less than 1. These results indicated that there was a synergistic antioxidant effect between procyanidins combined with α-tocopherol, which will show promising prospects in practical applications. In addition, particle size differentiation and morphology agglomeration were observed at different time points of antioxidant activity determination (0, 48, 96 h).

Ultrasound-Assisted Encapsulation of Phytochemicals for Food Applications: A Review

The use of phytochemicals as natural food additives is a topic of interest for both academic and food industry communities. However, many of these substances are sensitive to environmental conditions. For this reason, encapsulation is usually performed prior to incorporation into food products. In this sense, ultrasound-assisted encapsulation is an emerging technique that has been gaining attention in this field, bringing important advantages for the production of functional food products. This review article covered applications published in the last five years (from 2019 to 2023) on the use of ultrasound to encapsulate phytochemicals for further incorporation into food. The ultrasound mechanisms for encapsulation, its parameters, such as reactor configuration, frequency, and power, and the use of ultrasound technology, along with conventional encapsulation techniques, were all discussed. Additionally, the main challenges of existing methods and future possibilities were discussed. In general, ultrasound-assisted encapsulation has been considered a great tool for the production of smaller capsules with a lower polydispersity index. Encapsulated materials also present a higher bioavailability. However, there is still room for further developments regarding process scale-up for industrial applications. Future studies should also focus on incorporating produced capsules in model food products to further assess their stability and sensory properties.

Effect of Liposomal Encapsulation and Ultrasonication on Debittering of Protein Hydrolysate and Plastein from Salmon Frame

The impacts of liposomal encapsulation on the bitterness of salmon frame protein hydrolysate (SFPH) and salmon frame protein plastein (SFPP) with the aid of ultrasound (20% amplitude, 750 W) for different time intervals (30, 60 and 120 s) were investigated. Liposomes loaded with 1% protein hydrolysate (L-PH1) and 1% plastein (L-PT1) showed the highest encapsulation efficiency and the least bitterness (p < 0.05). Ultrasonication for longer times reduced encapsulation efficiency (EE) and increased bitterness of both L-PH1 and L-PT1 along with a reduction in particle size. When comparing between L-PH1 and L-PT1, the latter showed less bitterness due to the lower bitterness in nature and higher entrapment of plastein in the liposomes. In vitro release studies also showed the delayed release of peptides from L-PT1 in comparison to the control plastein hydrolysate. Therefore, encapsulation of liposomes with 1% plastein could be an efficient delivery system for improving the sensory characteristics by lowering the bitterness of protein hydrolysates.

Oral Administration of Ethanolic Extract of Shrimp Shells-Loaded Liposome Protects against Aβ-Induced Memory Impairment in Rats

Alzheimer's disease is characterized by a progressive loss of memory and cognition. Accumulation of amyloid-beta (Aβ) in the brain is a well-known pathological hallmark of the disease. In this study, the ethanolic extract of white shrimp (Litopenaous vannamei) shells and the ethanolic extract-loaded liposome were tested for the neuroprotective effects on Aβ_1-42-induced memory impairment in rats. The commercial astaxanthin was used as a control. Treatment with the ethanolic extract of shrimp shells (EESS) at the dose of 100 mg/kg BW showed no protective effect in Aβ-treated rats. However, treatment with an EESS-loaded liposome at the dose of 100 mg/kg BW significantly improved memory ability in Morris water maze and object recognition tests. The beneficial effect of the EESS-loaded liposome was ensured by the increase of the memory-related proteins including BDNF/TrkB and pre- and post-synaptic protein markers GAP-43 and PSD-95 as well as pErk1/2/Erk1/2 in the cortex and hippocampus. These findings indicated the neuroprotective effects of the EESS-loaded liposome on Aβ-induced memory impairment in rats. It produced beneficial effects on learning behavior probably through the function of BDNF/TrkB/pErk1/2/Erk1/2 signaling pathway and subsequently the upregulation of synaptic proteins. The present study provided evidence that the neuroprotective property of the ESSE-loaded liposome could be a promising strategy for AD protection.

The Molecular Mechanism of Polyphenols with Anti-Aging Activity in Aged Human Dermal Fibroblasts

Skin is the largest organ in the body comprised of three different layers including the epidermis, dermis, and hypodermis. The dermis is mainly composed of dermal fibroblasts and extracellular matrix (ECM), such as collagen and elastin, which are strongly related to skin elasticity and firmness. Skin is continuously exposed to different kinds of environmental stimuli. For example, ultraviolet (UV) radiation, air pollutants, or smoking aggravates skin aging. These external stimuli accelerate the aging process by reactive oxygen species (ROS)-mediated signaling pathways and even cause aging-related diseases. Skin aging is characterized by elasticity loss, wrinkle formation, a reduced dermal-epidermal junction, and delayed wound healing. Thus, many studies have shown that natural polyphenol compounds can delay the aging process by regulating age-related signaling pathways in aged dermal fibroblasts. This review first highlights the relationship between aging and its related molecular mechanisms. Then, we discuss the function and underlying mechanism of various polyphenols for improving skin aging. This study may provide essential insights for developing functional cosmetics and future clinical applications.