Performance of oil-in-water emulsions stabilized by different types of surface-active components

In vitro digestive behavior of emulsifier-stabilized excipient emulsions affects the bioaccessibility of flavonoids

BACKGROUND

Flavonoids, found in common vegetables and fruits, have health benefits that are often limited by their low bioavailability. Excipient emulsions provide an effective strategy to overcome these obstacles. However, the nature of the emulsifier used to formulate excipient emulsions and the chemical structure of the flavonoids both affect the bioaccessibility of the flavonoids.

RESULTS

The purpose of this study was to investigate the impact of the interfacial properties of excipient emulsions on the in vitro gastrointestinal fate of representative structural flavonoids (quercetin, kaempferol, and apigenin) through the INFOGEST method. Tween 80 (TW80) (a nonionic surfactant) was more effective at reducing the oil-water interfacial tension than whey protein isolate (WPI) (a protein-based emulsifier) or octenyl succinic anhydride (OSA)-modified starch (MS) (a polysaccharide-based emulsifier). Moreover, TW80 created excipient emulsions with smaller oil droplets, which were more resistant to oral and gastric conditions. The WPI-emulsions underwent severe flocculation in the gastric phase, leading to an appreciable increase in particle size (from 220 to 3000 nm). The TW80-coated oil droplets were more digestible than WPI- or MS-coated ones. This was attributed to the larger lipid surface area for lipase attachment. The bioaccessibility of quercetin, kaempferol, and apigenin was also affected by emulsifiers: TW 80 (25% to 45%) > WPI (14% to 29%) ≈ MS (15% to 25%). Flavonoid bioaccessibility appeared to be related to their molecular properties.

CONCLUSION

This study provides guidance for the design of effective excipient emulsions to enhance the bioavailability of flavonoids. © 2024 Society of Chemical Industry.

Peptide-Based Biomimetic Condensates via Liquid-Liquid Phase Separation as Biomedical Delivery Vehicles

Biomolecular condensates are dynamic liquid droplets through intracellular liquid-liquid phase separation that function as membraneless organelles, which are highly involved in various complex cellular processes and functions. Artificial analogs formed via similar pathways that can be integrated with biological complexity and advanced functions have received tremendous research interest in the field of synthetic biology. The coacervate droplet-based compartments can partition and concentrate a wide range of solutes, which are regarded as attractive candidates for mimicking phase-separation behaviors and biophysical features of biomolecular condensates. The use of peptide-based materials as phase-separating components has advantages such as the diversity of amino acid residues and customized sequence design, which allows for programming their phase-separation behaviors and the physicochemical properties of the resulting compartments. In this Perspective, we highlight the recent advancements in the design and construction of biomimicry condensates from synthetic peptides relevant to intracellular phase-separating protein, with specific reference to their molecular design, self-assembly via phase separation, and biorelated applications, to envisage the use of peptide-based droplets as emerging biomedical delivery vehicles.

Polyglycerol polyricinoleate and lecithin stabilized water in oil nanoemulsions for sugaring Beijing roast duck: Preparation, stability mechanisms and color improvement

Traditional Beijing roast duck often suffers from uneven color and high sugar content after roasting. Water-in-oil (W/O) nanoemulsion is a promising alternative to replace high concentration of sugar solution used in sugaring process according to similarity-intermiscibility theory. Herein, 3% of xylose was embedded in the aqueous phase of W/O emulsion to replace 15% maltose solution. W/O emulsions with different ratios of lecithin (LEC) and polyglycerol polyricinoleate (PGPR) were constructed by high-speed homogenization and high-pressure homogenization. Distribution and penetration extent of solutions and emulsions through the duck skin, as well as the color uniformity of Beijing roast duck were analyzed. Emulsions with LEC:PGPR ratios of 1:3 and 2:2 had better stability. Stable interfacial film and spatial structure were important factors influencing emulsion stabilization. The stable W/O emulsions could more uniformly distribute onto the surface of duck skin and longitudinally penetrate through the skin than solutions.

Preparation and quality evaluation of a volatile oil microemulsion from Flos magnoliae and Centipeda minima

In order to improve the water solubility of the volatile oils extracted from Flos magnoliae (FM) and Centipeda minima (CM), they were prepared as a microemulsion (ME), which were then used in the development of an FM and CM volatile oil ME for the treatment of allergic rhinitis (AR). ME was prepared by phase inversion emulsification, and the prescription factors such as emulsifier, co‑emulsifier, oil phase, Km, which represents the ratio of the mass of emulsifier to that of the co‑emulsifier, and preparation factors such as temperature affecting the formation of the ME were selected according to the formation area of ME in a pseudo‑ternary phase diagram. The quality of the ME was evaluated based on its appearance, particle size, Zeta potential and stability. The content of eucalyptol in ME was determined by gas chromatography‑mass spectrometry (GC‑MS). The cumulative permeability of the ME within 24 h was measured with a transdermal diffusion tester. The results revealed that the best formula for preparation of the ME was as follows: Castor oil polyoxyethylene ether (EL‑40) was the emulsifier; the co‑emulsifier was anhydrous ethanol; the Km was 2:1; the mixed phase of volatile oil and isopropyl myristate with mass ratio of 1:1 was used as oil phase; and the preparation temperature was 25˚C. The content of eucalyptol in the ME was 2.57 mg/g, and the cumulative permeability of the ME in 24 h was significantly increased compared with that of the reference oil solution. The appearance of the ME was uniform, and the solution was transparent. In conclusion, compared with traditional preparations, FM and CM volatile oil ME is a novel, improved and more effective preparation for the treatment of AR.