Effects of flavonoids on physical and oxidative stability of soybean oil O/W emulsions

Origanum majorana L. as Flavoring Agent: Impact on Quality Indices, Stability, and Volatile and Phenolic Profiles of Extra Virgin Olive Oil (EVOO)

The flavoring of olive oils with aromatic plants is commonly used to enrich the oils with aromatic and antioxidant compounds. Origanum majorana L. was applied as a flavoring agent for extra virgin olive oil (EVOO), at concentrations of 20 g L-1 and 40 g L-1, via ultrasound-assisted maceration. The aim of this study was to evaluate the impact of flavoring on the EVOOs' quality indices, oxidative stability, and antioxidant, antiradical and antifungal activities, as well as on the oils' volatile and phenolic profile. The flavored EVOO maintained the quality indices (free fatty acids, peroxide value, extinction coefficients) below the maximum permitted levels, whereas the addition of marjoram enhanced the oxidative stability, the levels of chlorophyll and b-carotene and the total phenolic content. The incorporation of marjoram into the EVOO did not have a significant impact on the antioxidant and antiradical activities. Concerning the antifungal activity, no Zygosaccharomyces bailli cell growth was observed for two weeks in a mayonnaise prepared with the flavored EVOO at a 40 g L-1 concentration. SPME-GC-MS analysis revealed the presence of 11 terpene compounds (hydrocarbon and oxygenated monoterpenes) that had migrated from marjoram in the flavored EVOO. Twenty-one phenolic compounds were tentatively characterized by LC-QToF-MS in the EVOO samples; however, hesperetin and p-coumaric acid, originating from marjoram, were only detected in the flavored EVOO.

Exploring Phenolic Compounds in Crop By-Products for Cosmetic Efficacy

Phenolic compounds represent a group of secondary metabolites that serve essential functions in plants. Beyond their positive impact on plants, these phenolic metabolites, often referred to as polyphenols, possess a range of biological properties that can promote skin health. Scientific research indicates that topically using phenolics derived from plants can be advantageous, but their activity and stability highly depend on storage of the source material and the extraction method. These compounds have the ability to relieve symptoms and hinder the progression of different skin diseases. Because they come from natural sources and have minimal toxicity, phenolic compounds show potential in addressing the causes and effects of skin aging, skin diseases, and various types of skin damage, such as wounds and burns. Hence, this review provides extensive information on the particular crops from which by-product phenolic compounds can be sourced, also emphasizing the need to conduct research according to proper plant material storage practices and the choice of the best extracting method, along with an examination of their specific functions and the mechanisms by which they act to protect skin.

Orange Mesocarp Extract as a Natural Surfactant: Impact on Fluid-Fluid and Fluid-Rock Interactions during Chemical Flooding

Surfactant flooding has suffered a huge setback owing to its cost and the ecotoxic nature of synthetic surfactants. The potential of natural surfactants for enhanced oil recovery has attracted a great deal of research interest in recent times. In this research, orange mesocarp extract (OME) was studied as a potential green surface-active agent in recovering heavy oil. The extract obtained from the orange (Citrus sinensis) mesocarp using alkaline water as solvent was characterized by Fourier transform infrared spectrophotometry . Phase behavior was studied to ascertain its stability at 100 °C and compatibility with divalent ions. Microemulsion system, interfacial tension, optimal salinity, and critical micelle concentration were analyzed to evaluate the surfactant. Oil displacement analysis using an oil-wet sandstone medium under reservoir conditions was performed. Surfactant adsorption mechanism on the core was investigated at atmospheric conditions (28 °C) using the Langmuir, Freundlich, Temkin, and linear isotherm models, while the kinetics pattern was modeled with the pseudo-first-order, pseudo-second-order, intraparticle diffusion, and Elovich models. Results showed fluid compatibility and bicontinuous microemulsion at varied temperatures. Surfactant flooding produced an additional oil recovery of 44 and 29.1%, which confirms the capability of this natural surfactant in recovering heavy oil. Langmuir isotherm gave the highest correlation coefficient (R2) value of 0.982, indicating that the adsorption of the surfactant (OME) on the core occurred at specific homogeneous sites, which when occupied by a higher surfactant concentration will disallow further adsorption on these sites. From the R2 values, almost all of the kinetic models corroborated good adsorption capacity of the core and an affinity for the surfactant at low concentration. This indicates that low concentration of the surfactant may not favor the enhanced oil recovery operation due to adsorption in the reservoirs, hence the need to flood at a higher surfactant concentration.

Review on the Antioxidant Activity of Phenolics in o/w Emulsions along with the Impact of a Few Important Factors on Their Interfacial Behaviour

This review paper focuses on the antioxidant properties of phenolic compounds in oil in water (o/w) emulsion systems. The authors first provide an overview of the most recent studies on the activity of common, naturally occurring phenolic compounds against the oxidative deterioration of o/w emulsions. A screening of the latest literature was subsequently performed with the aim to elucidate how specific parameters (polarity, pH, emulsifiers, and synergistic action) affect the phenolic interfacial distribution, which in turn determines their antioxidant potential in food emulsion systems. An understanding of the interfacial activity of phenolic antioxidants could be of interest to food scientists working on the development of novel food products enriched with functional ingredients. It would also provide further insight to health scientists exploring the potentially beneficial properties of phenolic antioxidants against the oxidative damage of amphiphilic biological membranes (which link to serious pathologic conditions).

A Novel Functional Emulsifier Prepared with Modified Cassava Amylose with Octenyl Succinic Anhydride and Quercetin: Preparation and Application in the Pickering Emulsion

An emulsifier with a targeted antioxidant effect was prepared using the inclusion complexes of octenyl succinic anhydride (OSA)-modified cassava amylose (CA) and quercetin (Q). The designed emulsifier, a carbohydrate polymer-flavonoid complex, exhibited both amphiphilic and antioxidant properties. To investigate the physical and oxidation stabilities of the prepared emulsion, three types of emulsions were prepared: primary emulsions stabilized by enzyme-modified starch, secondary emulsions stabilized by OSA-CA, and tertiary emulsions stabilized by Q-encapsulated complexes (OSA-CA/Q). The structural characteristics of CA, OSA-CA, and OSA-CA/Q were investigated by scanning electron microscopy, Fourier transform infrared spectrometry, and small-angle X-ray scattering analysis. The stabilities of the emulsions were evaluated based on their particle size distribution, zeta potential, creaming stability, and peroxide value. The results showed that the secondary and tertiary emulsions exhibited a relatively narrower particle size distribution than the primary emulsions, but the particle size distribution of the tertiary emulsions was the narrowest (10.42 μm). Moreover, the secondary and tertiary emulsions had lower delamination indices than the primary emulsions after 7 days of storage. The results obtained from the antioxidant experiments indicated that OSA-CA/Q exhibited good oxidation stability for application in emulsion systems.

A comprehensive review on polarity, partitioning, and interactions of phenolic antioxidants at oil-water interface of food emulsions

There has been a growing interest in developing effective strategies to inhibit lipid oxidation in emulsified food products by utilization of natural phenolic antioxidants owing to their growing popularity over the past decades. However, due to the complexity of emulsified systems, the inhibition mechanism of phenolic antioxidants against lipid oxidation is rather complicated and not yet fully understood. In order to highlight the importance of polarity of phenolic antioxidants in emulsified systems according to the polar paradox, this review covers the recent progress on chemical, enzymatic, and chemoenzymatic lipophilization techniques used to modify the polarity of antioxidants. The partitioning behavior of phenolic antioxidants at the oil-water interface, which can be influenced by the presence of synthetic surfactants and/or antioxidant emulsifiers (e.g., polysaccharides, proteins, and phospholipids), is discussed. In addition, the emerging phenolic antioxidants among phenolic acids, flavonoids, tocopherols, and stilbenes applied in food emulsions are elaborated. As well, the interactions of polar-nonpolar antioxidants are stressed as a promising strategy to induce synergistic interactions at oil-water interface for improved oxidative stability of emulsions.

Review of Functional and Pharmacological Activities of Berries

Functional plant-based foods (such as fruits, vegetables, and berries) can improve health, have a preventive effect, and diminish the risk of different chronic diseases during in vivo and in vitro studies. Berries contain many phytochemicals, fibers, vitamins, and minerals. The primary phytochemicals in berry fruits are phenolic compounds including flavonoids (anthocyanins, flavonols, flavones, flavanols, flavanones, and isoflavonoids), tannins, and phenolic acids. Since berries have a high concentration of polyphenols, it is possible to use them for treating various diseases pharmacologically by acting on oxidative stress and inflammation, which are often the leading causes of diabetes, neurological, cardiovascular diseases, and cancer. This review examines commonly consumed berries: blackberries, blackcurrants, blueberries, cranberries, raspberries, black raspberries, and strawberries and their polyphenols as potential medicinal foods (due to the presence of pharmacologically active compounds) in the treatment of diabetes, cardiovascular problems, and other diseases. Moreover, much attention is paid to the bioavailability of active berry components. Hence, this comprehensive review shows that berries and their bioactive compounds possess medicinal properties and have therapeutic potential. Nevertheless, future clinical trials are required to study and improve the bioavailability of berries' phenolic compounds and extend the evidence that the active compounds of berries can be used as medicinal foods against various diseases.

Emulsification and oxidation stabilities of DAG-rich algae oil-in-water emulsions prepared with the selected emulsifiers

BACKGROUND

Diacylglycerol (DAG) reduces body weight, suppresses body fat accumulation, and lowers the blood lipid concentration, and docosahexaenoic acid (DHA) can reduce the risk of occurrence of coronary artery diseases.

RESULTS

DAG-rich algae oil with a high DHA content (55.9%) was synthesized via the lipase-catalyzed glycerolysis of algae oil, which consisted of triacylglycerol (43.9 mol%), DAG (40.9 mol%), and monoacylglycerol (15.2 mol%). The DAG-rich algae oil-in-water emulsions were prepared using three emulsifiers [whey protein concentrate (WPC), Tween80, and Tween80 + Span80]. The WPC-emulsion formed a thicker serum layer (6.67% at day 51) and larger oil droplets (d₃₂ , 0.37 μm at day 28) than the Tween80- and Tween80 + Span80-emulsions (3.33-4.17%; 0.26 μm), and an upper cream layer with excess oil droplets was observed in only the WPC-emulsion, indicating that WPC-emulsion possesses the lowest emulsification stability. The hydroperoxide value and reduction rate of the DHA content were higher in the WPC-emulsions than in the Tween80- and Tween80 + Span80-emulsions during storage, which suggested that the WPC-emulsion had the lowest oxidation stability.

CONCLUSION

The DAG-rich algae oil-in-water emulsion prepared with suitable emulsifiers, such as non-ionic emulsifiers, would have excellent emulsification and oxidative stabilities and provides a health benefit for special purposes in the food processing industry. © 2019 Society of Chemical Industry.

Physical and Chemical Stability of Formulations Loaded with Taxifolin Tetra-octanoate

Chemically stable ester derivatives of taxifolin have become a focus of interest for their role in the satisfactory effects on human health. Accordingly, the aim of this study was to evaluate the physical and chemical stability of different formulations containing 0.02% taxifolin tetra-octanoate, which was proved to possess higher inhibitory effect on tyrosinase activity compared with taxifolin in a cell-free system. In the studies of physical stability, a Brookfield viscometer was used to determine rheological behavior of formulations containing taxifolin tetra-octanoate, and a portable pH meter was used to determine pH change. Moreover, chemical stability was determined by HPLC with UV detection. Formulations were evaluated for 12 weeks stored at 25 and 40°C. Results showed that storage time had no significant influence on viscosity of the formulations containing taxifolin tetra-octanoate, and pH value was relatively stable, which was within the limits of normal skin pH range. In the chemical stability studies, taxifolin tetra-octanoate in the essence formulation was most unstable at 40°C with about 81% degradation in 12 weeks of storage, however, the percentage of remaining taxifolin tetra-octanoate in cream formulation stored for 12 weeks at 25°C was the highest, about 93%. The results in this study may contribute to the development of more stable formulations containing taxifolin tetra-octanoate.

Byproduct Generated During the Elaboration Process of Isotonic Beverage as a Natural Source of Bioactive Compounds

Agro-industrial byproducts are considered good sources of macronutrients and phytochemicals. Fruit and vegetable residues (FVR), obtained after the production of an isotonic beverage, have previously been characterized containing 80% insoluble dietary fibers from total fibers (48.4%), 26% available carbohydrates, 9.5% proteins and 5% lipids. Nevertheless, fruit and vegetables provide phytochemicals which have been related to human health such as phenolic compounds. The loss of specific compounds over the production process is related to their partitioning between fruit and vegetables and byproducts. However, phenolic profile of FVR remains unknown. This work is focused on the evaluation of FVR as a natural source of these bioactive compounds. For this purpose, pressurized liquid extraction (PLE) has been proposed as extraction technique for recovering phenolic compounds from FVR. The experimental variables were temperature and percentage of solvent (ethanol and water). Phenolic compounds extracts were characterized by UPLC-ESI-Q-TOF-MS and a discussion about phenolic and macronutrient interactions was established. Globally, 88 compounds were tentatively identified: phenolic acids (28), flavonoids (32), and other polyphenols (28). The PLE conditions applied yielded different breaking matrix-analyte interactions leading to an increase in the number of compounds. The highest phenolic acids content was achieved with high temperature while lower temperatures were more efficient in extracting flavonoid. By establishing the phenolics profile in food byproducts such as FVR, it is possible to more effectively apply these byproducts as nutraceutical, food or pharmaceutical ingredients.

PRACTICAL APPLICATION

Flow diagram of bioactive compounds recovering from isotonic beverage byproduct is proposed using pressurized liquid extraction. The plant-bioactives mechanism relies on fruit and vegetable byproducts changes under different extraction conditions. The obtained extracts can most effectively be applied as nutraceuticals or as ingredients in food or pharmaceutical inputs.