Biopolymer-based particles as stabilizing agents for emulsions and foams

Surface interaction at the biomaterial–cell interface is essential for a variety of cellular functions, such as adhesion, proliferation, and differentiation. Nevertheless, changes in the biointerface enable to trigger specific cell signaling and result in different cellular responses. In order to manufacture biomaterials with higher functionality, biomaterials containing immobilized bioactive ligands have been widely introduced and employed for tissue engineering and regenerative medicine applications. Moreover, a number of physical and chemical strategies have been used to improve the functionality of biomaterials and specifically at the material interface. Here, the interactions between materials and cells at the interface levels are described. Then, the importance of surface properties in cell function is discussed and recent methods for surface modifications are systematically highlighted. Additionally, the impact of bulk material properties on the cellular responses is briefly reviewed.

https://www.onlinelibrary.wiley.com/doi/epdf/10.1002/admi.201900572

Controlling Cell Behavior through the Design of Biomaterial Surfaces: A Focus on Surface Modification Techniques

In recent years, natural plant products are gaining popularity in preventing various diseases. Garlic is one of the most extensively researched product for investigating its beneficial effects. Potential health benefits of allium vegetables, in particular garlic (Allium sativum) has its origin in antiquity. It has acquired a reputation as a formidable prophylactic and therapeutic medicinal agent in the folklore of many cultures, over the centuries. The bioactive components of garlic are mainly responsible for the healing properties. The major physiological role of garlic are its antimicrobial, anticancer, antioxidant, immune boosting, antidiabetic, hepatoprotective, antifibrinolytic and antiplatelet aggregatory activity and its potential role in preventing cardiovascular diseases. The acclaimed health benefits of chemical constituents of garlic in treating various disorders have been investigated both in animals as well as in humans. This article reviews the current knowledge regarding the physiological role of garlic in various disease states.

Bioactive components of garlic and their physiological role in health maintenance: A review

Nitric oxide-activated hydrogen sulfide is essential for cadmium stress response in bermudagrass (Cynodon dactylon (L). Pers.)

Background Developing novel food structures is nowadays becoming an attractive technology for food product innovation because they can be used to control textural properties, oral processing and perception, as well as biofunctionality in the human body. Proteins and polysaccharides are among the most abundant natural raw materials that can be used for creating novel food structures owing to their supramolecular interactions driven by attractive or repulsive forces. These two classes of biopolymers can be used to create different types of colloidal systems with unique properties, such as nano- or microparticles, hydrogels, films, emulsions, oil-filled hydrogels, foams, and oleogels, to name a few. Scope and approach In this review, we discuss a range of functional colloids which can be fabricated by exploiting spontaneous interactions of proteins and polysaccharides. Besides, the fundamental theories of proteins and polysaccharides interactions that can affect the structural formation are described. Furthermore, potential food applications of some selective functional colloids are also discussed with illustrative examples. Key findings and conclusions The synergistic interactions of proteins and polysaccharides in their mixed system and a more complex system where a hydrophobic phase is present, could be employed to obtain various colloidal structures with numerous promising applications in the food industry.

Functional colloids from proteins and polysaccharides for food applications

Dynamic and viscoelastic interfacial behavior of β-lactoglobulin microgels of varying sizes at fluid interfaces

In ancient times, plants were recognized for their medicinal properties. Later, the arrival of synthetic drugs pushed it to the backstage. However, from being merely used for food, plants are now been widely explored for their therapeutic value. The current study explores the potential of skin and flesh extracts from a hard-necked Rocambole variety of purple garlic in preventing cardiomyocyte hypertrophy and cell death. Norepinephrine (NE) was used to induce hypertrophy in adult rat cardiomyocytes pretreated with garlic skin and flesh extracts. Cell death was measured as ratio of rod to round shaped cardiomyocytes. Fluorescent probes were used to measure apoptosis and oxidative stress in cardiomyocytes treated with and without extracts and NE. Pharmacological blockade of nitric oxide (NO) and hydrogen sulfide (H2S) were used to elucidate the mechanism of action of garlic extracts. Garlic extract samples were also tested for alliin and allicin concentrations. Exposure of cardiomyocytes to NE induced an increase in cell size and cell death; this increase was significantly prevented upon treatment with garlic skin and flesh extracts. Norepinephrine increased apoptosis and oxidative stress in cardiomyocytes which was prevented upon pretreatment with skin and flesh extracts; NO, and H2S blockers significantly inhibited this beneficial effect. Allicin and alliin concentration were significantly higher in garlic flesh extract when compared to the skin extract. These results suggest that both skin and flesh garlic extracts are effective in preventing NE induced cardiomyocyte hypertrophy and cell death. Reduction in oxidative stress may also play an important role in the anti-hypertrophic and anti-apoptotic properties of garlic extracts. These beneficial effects may in part be mediated by NO and H2S.

/pdf/garlic-extracts-prevent-oxidative-stress-hypertrophy-and-3metxn6is2.pdf

Garlic extracts prevent oxidative stress, hypertrophy and apoptosis in cardiomyocytes: a role for nitric oxide and hydrogen sulfide

Hypothesis Factors influencing fabrication and size of microgels formed from β-lactoglobulin with or without pectin can tune selected attributes for material applications. Protein aggregation was expected to be influenced by pH, added anions, and reducing agents, while ionic strength was expected to be more influenced by electrostatically interacting pectin. Experiments Turbidity measurements during thermal aggregation to form microgels were determined for pure β-lactoglobulin as a function of pH, added ionic strength, anion type (chloride, sulfate, and thiocyanate), and reducing agent concentration. β-lactoglobulin and pectin complexation pH values and thermal aggregation were determined by turbidity measurements with added potassium chloride, sulfate, and thiocyanate. Microgel size and morphology were determined by light scattering and atomic force microscopy, respectively. Findings Thermal aggregation of pure β-lactoglobulin increased with decreased pH, reducing conditions, and increased ionic strength with no observed anion effect. β-lactoglobulin microgel radii increased from 86 to 115 nm with decreasing pH and increased to 124 nm in reducing conditions, while salts promoted agglomeration. Increased ionic strength (0–100 mmol/kg) decreased β-lactoglobulin-pectin complexation pH from 5.40 to 5.00, while first increasing and then decreasing thermal aggregation. Thermal aggregation and microgel size were greatest with potassium thiocyanate, followed by potassium chloride and potassium sulfate.

Control of thermal fabrication and size of β-lactoglobulin-based microgels and their potential applications.

Hypothesis Microgels assembled from the protein β-lactoglobulin are colloidal structures with potential applications in food materials. Modifying the internal crosslinking within these microgels using enzymatic or chemical treatments should affect dissolution, swelling, and viscous attributes under strongly solvating conditions. Experiments Microgels were treated with citric acid, glutaraldehyde and transglutaminase to induce cross-linking or with tris(2-carboxyethyl)phosphine to reduce disulfide linkages. Change in hydrodynamic particle size due to acidic pH, alkaline pH, ionic strength, osmolyte concentration, ethanol, urea, sodium dodecyl sulfate, and reducing agents was evaluated by light scattering measurements. Changes in microgel nanomechanical properties were evaluated via force spectroscopic measurements in water. Findings Average microgel size increased ∼20% in alkaline pH and with ethanol contents above 10%, and decreased ∼20% with sucrose contents above 10%. Cross-linking by glutaraldehyde and transglutaminase prevented size increases in alkaline pH. Microgel plasticity and elastic modulus were unaffected by treatments. Microgels treated with glutaraldehyde were found to have much greater stability to urea, sodium dodecyl sulfate, and reducing agents when compared to other samples. Even without cross-linking, microgels remained stable against precipitation and dissolution over a wide range conditions, indicating their broad utility as colloidal stabilizers, texture modifiers or controlled release agents in food or other applications.

Effect of crosslinking on the physical and chemical properties of β-lactoglobulin (Blg) microgels.

The power of oriented electrostatic fields (ESFs) to influence chemical bonding and reactivity is a phenomenon of rapidly growing interest. The presence of strong ESFs has recently been implicated as one of the most significant contributors to the activity of select enzymes, wherein alignment of a substrate's changing dipole moment with a strong, local electrostatic field has been shown to be responsible for the majority of the enzymatic rate enhancement. Outside of enzymology, researchers have studied the impacts of “internal” electrostatic fields via the addition of ionic salts to reactions and the incorporation of charged functional groups into organic molecules (both experimentally and computationally), and “externally” via the implementation of bulk fields between electrode plates. Incorporation of charged moieties into homogeneous inorganic complexes to generate internal ESFs represents an area of high potential for novel catalyst design. This field has only begun to materialize within the past 10 years but could be an area of significant impact moving forward, since it provides a means for tuning the properties of molecular complexes via a method that is orthogonal to traditional strategies, thereby providing possibilities for improved catalytic conditions and novel reactivity. In this perspective, we highlight recent developments in this area and offer insights, obtained from our own research, on the challenges and future directions of this emerging field of research.

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Ryan W. Murphy

Papers

Dynamic and viscoelastic interfacial behavior of β-lactoglobulin microgels of varying sizes at fluid interfaces

Garlic extracts prevent oxidative stress, hypertrophy and apoptosis in cardiomyocytes: a role for nitric oxide and hydrogen sulfide

Control of thermal fabrication and size of β-lactoglobulin-based microgels and their potential applications.

Effect of crosslinking on the physical and chemical properties of β-lactoglobulin (Blg) microgels.

Oriented internal electrostatic fields: an emerging design element in coordination chemistry and catalysis