Publications by authors named "Constantinos V Nikiforidis"

Hypothesis: Plant-based proteins offer a sustainable solution for stabilizing multiphase food materials like edible foams and emulsions. However, challenges in understanding and engineering plant protein-stabilized interfaces persist, mostly because of the commonly poorer functionality and complex composition of the respective protein isolates. We hypothesize that part of the limited understanding is related to the lack of experimental data on the length-scale of the thin liquid film that separates two neighboring bubbles.

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Article Synopsis
  • Oleosomes are lipid droplets that store energy and have a membrane made of phospholipids and proteins, which can carry therapeutic substances.
  • The study looked at how curcumin, a compound that can be loaded into oleosomes, affects the mechanical properties of their membranes.
  • Results showed that curcumin increases interactions within the membrane, potentially allowing for better-designed oleosome-based treatments.
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Hypothesis: Oilseeds use triacylglycerides as main energy source, and pack them into highly stable droplets (oleosomes) to facilitate the triacylglycerides' long-term storage in the aqueous cytosol. To prevent the coalescence of oleosomes, they are stabilized by a phospholipid monolayer and unique surfactant-shaped proteins, called oleosins. In this study, we use state-of-the-art interfacial techniques to reveal the function of each component at the oleosome interface.

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Oleosomes are natural lipid droplets that can be extracted intact from oil seeds, forming oil/water emulsions. Their lipid cores, surrounded by a monolayer of phospholipids and proteins, make oleosomes suitable as carriers of hydrophobic bioactive compounds like cannabidiol (CBD). As CBD is crystalline at room temperature, it first has to be liquified to allow better encapsulation.

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Liquid crystals (LCs) are emerging as novel platforms for chemical, physical, and biological sensing. They can be used to detect biological amphiphiles such as lipids, fatty acids, digestive surfactants, and bacterial endotoxins. However, designing LC-based sensors in a manner that preserves their sensitivity and responsiveness to these stimuli, and possibly improves biocompatibility, remains challenging.

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The extraction of oil from oilseeds in intact oleosomes is one of the suggested processes that could replace the extraction of oil by pressing and solvent extraction, being milder, environmentally less impactful and potentially more efficient in its use of resources. This study assesses the latter using an exergy assessment of oleosome extraction for food emulsions. The contribution of each part of the process to the overall impact was investigated.

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Article Synopsis
  • * The study focuses on plant-derived lipid droplets, or oleosomes, and their ability to carry hydrophobic therapeutics like curcumin, showing that curcumin can easily move into these droplets.
  • * Research techniques demonstrated that curcumin accumulates both at the oleosome interface and within its core, revealing important insights into how plant lipid droplets can be utilized as drug carriers.
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  • The study investigates two protein families in rapeseed, cruciferins and napins, and how their structural differences affect oil-water interface stabilization.
  • Through experiments using techniques like SEC and DSC, the researchers evaluated protein properties and the mechanical behavior of oil-water interfaces, as well as the emulsifying capabilities of these proteins in different mixtures.
  • Findings reveal that cruciferins create more stable oil droplets than napins, which leads to a higher resistance against coalescence, highlighting the distinct roles each protein plays in emulsions.
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Hypothesis: Oleosomes are natural oil droplets with a unique phospholipid/protein membrane, abundant in plant seeds, from which they can be extracted and used in emulsion-based materials, such as foods, cosmetics and pharmaceutics. The lubrication properties of such materials are essential, on one hand, due to the importance of the in-mouth creaminess for the consumed products or the importance of spreading the topical creams. Therefore, here, we will evaluate the lubrication properties of oleosomes, and how these properties are affected by the components at the oleosome membrane.

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Oleosins are proteins with a unique central hydrophobic hairpin designed to stabilize lipid droplets (oleosomes) in plant seeds. For efficient droplet stabilization, the hydrophobic hairpin with a strong affinity for the apolar droplet core is flanked by hydrophilic arms on each side. This gives oleosins a unique surfactant-like shape making them a very interesting protein.

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Article Synopsis
  • Lipid droplets known as oleosomes can change size by absorbing or releasing lipids, showcasing their flexible membrane, which could be useful for creating responsive droplets.
  • Researchers extracted oleosomes from rapeseeds to form a stable oil-in-water emulsion, confirming the ability of the membrane molecules to rearrange when more surface area is available.
  • The study demonstrated that the weak lateral interactions in oleosome membranes allow them to destabilize when placed on hydrophobic surfaces, leading to potential applications in targeted release for food, pharmaceuticals, and cosmetics.
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  • Oleosomes are natural oil droplets found in all organisms, especially abundant in oilseeds, and can be used in food, cosmetics, and emulsions after extraction.
  • Research focused on their emulsifying ability using oleosomes from rapeseeds, resulting in stable oil-in-water emulsions at concentrations of 1.5 wt% or higher, with droplet sizes between 2.0 and 12.0 µm.
  • The study indicates that oleosomes aren't just stabilizing emulsions as whole particles, but their interfacial molecules can effectively stabilize oil-water surfaces, suggesting potential for natural emulsifiers in food and pharmaceuticals.
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Hollow microparticles (MPs) are of great relevance in the materials industry for a wide range of applications, such as catalysis, coatings, and delivery of theranostics. Here, we report the formation of hollow MPs through the assembly of lipoproteins in CaCO templates. Proteins interact in the pores of CaCO templates through attractive hydrophobic forces and form dense edges of hollow MPs.

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The formation of protein gel networks in aqueous systems is a result of protein intermolecular interactions after an energy input, like heating. In this research, we report that a redox reaction between Au ions and proteins can also lead to the formation of a protein gel network. Amino acids, like cysteine and tyrosine, get oxidized and form covalent bonds with neighboring protein molecules, while Au ions get reduced to Au and Au, nucleate and form gold nanoparticles.

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Hypothesis: Plant seeds store lipids in oleosomes, which are storage organelles with a triacylglycerol (TAG) core surrounded by a phospholipid monolayer and proteins. Due to their membrane components, oleosomes have an affinity for the air/oil-water interface. Therefore, it is expected that oleosomes can stabilise interfaces, and also compete with proteins for the air-water interface.

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Plants offer a vast variety of protein extracts, typically containing multiple species of proteins that can serve as building blocks of soft materials, like emulsions. However, the role of each protein species concerning the formation of emulsions and interfaces with diverse rheological properties is still unknown. Therefore, deciphering the role of the individual proteins in an extract is highly relevant, since it determines the optimal level of purification, and hence the sustainability aspects of the extract.

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Pea proteins are promising oil-in-water emulsifying agents at both neutral and acidic conditions. In an acidic environment, pea proteins associate to form submicrometer-sized particles. Previous studies suggested that the emulsions at acidic pH were stabilized due to a Pickering mechanism.

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The lipolytic activity in oil body creams as affected by recovery and washing protocols was investigated. The effect of thermal treatment on the hydrolytic activity and physical stability of fresh and aged (up to 30 days) oil body emulsions was studied. The use of alkaline pH solutions (9.

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Oleosomes are natural oil droplets, abundant in plants and more specifically in seeds, composing 20-50 wt% of their mass. The structure of oleosomes is the mechanism that seeds developed to safely store energy in the form of triacylglycerols and use it during germination. For this, the phospholipid/protein membrane that covers and protects the triacylglycerols has been wisely developed during evolution to grant them extreme stability against physical and chemical stresses.

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Oleosomes are storage vehicles of TAGs in plant seeds. They are protected with a phospholipid-protein monolayer and extracted with alkaline aqueous media; however, pH adjustment intensifies the extraction process. Therefore, the aim of this work was to investigate the extraction mechanism of rapeseed oleosomes at pH 7 and at the presence of monovalent and divalent cations (Na, K, Mg and Ca).

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Oleosomes are particles equipped with a sophisticated membrane, comprising a continuous monolayer of phospholipids and hydrophobic proteins, which covers the triglyceride core and grants them extreme physical and chemical stability. The noteworthy qualities of oleosomes have attracted strong interest for their incorporation in emulsion formulations; however, little is known about their emulsifying properties and their behaviour on interfaces. For these reasons, oleosomes were isolated from sunflower seeds (96.

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Despite significant progress toward the commercialization of biobased products, today's biorefineries are far from achieving their intended goal of total biomass valorization and effective product diversification. The problem is conceptual. Modern biorefineries were built around well-optimized, cost-effective chemical synthesis routes, like those used in petroleum refineries for the synthesis of fuels, plastics, and solvents.

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Previous studies have proved that the physical encapsulation of nutrients by the cell walls of plant foods modulates macronutrient bioaccessibility during human digestion. In this study, we investigated structural factors that modulate lipid hydrolysis during in vitro digestion of raw and roasted hazelnut particles and isolated oil bodies. Isolated oil bodies exhibited a significantly higher lipid hydrolysis compared to hazelnut particles.

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Proteins and phenols coexist in the confined space of plant cells leading to reactions between them, which result in new covalently bonded complex molecules. This kind of reactions has been widely observed during storage and processing of plant materials. However, the nature of the new complex molecules and their physicochemical properties are largely unknown.

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