The potential of almonds, hazelnuts, and walnuts SFE-CO2 extracts as sources of bread flavouring ingredients.

Nuts have been part of the human diet since our early ancestors, and their use goes beyond nutritional purposes, for example, as aromatic sources for dairy products. This work explores the potential of almond (Prunus dulcis (Mill.) DA Webb), hazelnut (Corylus avellana L.), and walnut (Juglans regia L.) extracts as sources of food flavouring agents, suggesting a new added-value application for lower quality or excess production fruits. The extracts were obtained by supercritical fluid extraction with carbon dioxide and characterized by: quantification of the volatile fraction by HS-SPME GC-MS; sensory perception and description; and cytotoxicity against Vero cells. All extracts revealed potential as flavouring ingredients due to terpene abundance. No significant differences were observed for the minimal sensory perception, in which the odour threshold values ranged from 8.3 × 10-4 to 6.9 × 10-3 µg·mL-1 for walnuts and almonds extracts, respectively. In contrast, the cytotoxic potential differed significantly among the extracts, and P. dulcis extract presented lower cytotoxicity. Notes as woody, fresh, and green were identified in the volatile intensifiers obtained from the P. dulcis extract. Thus, almond extract was identified as the most promising ingredient to increase the sensory value of food products, namely bread. This potential was verified by an increase in the odour perception of bread after adding 4 µL of extract to each 100 g of bread dough. The quantified eucalyptol and d-limonene terpenes - found in the P. dulcis extract - have improved the release of the pleasant and natural volatile compounds from bread crust and crumb compared to the control bread chemical and sensory profiles.

Chemical and organoleptic properties of bread enriched with Rosmarinus officinalis L.: The potential of natural extracts obtained through green extraction methodologies as food ingredients.

The potential of R. officinalis L. (RO) extracts as a source of aromas was accessed by hydrodistillation (HD) and supercritical fluid extraction using carbon dioxide (SFE-CO2), followed by a series of analysis: quantification by GC-MS, sensory perception and description, and cytotoxicity against Vero cells. The extracts shown abundancy of α-pinene, eucalyptol, S-verbenone and camphor, contributing for the green, fresh, citric, and woody as main sensory notes. The odour threshold (ODT) value (less than 3.0 × 10-3 µg·mL-1) and the cytotoxic potential (ca. 220 µg∙mL-1) defined the concentration range for food application. The most promising extract was added to bread doughs and the final volatile profile was characterised by GC-MS through HS-SPME over time. Among the 34 compounds found, furfural showed an evident contribution in the bread crust aroma, which persisted over four hours of storage, contributing to a pleasant bread fragrance according to the evaluators. This study aims to represent a stepping stone for the use of natural aromas as ingredients for the development of innovative food products.

Obtaining Aromatic Extracts from Portuguese Thymus mastichina L. by Hydrodistillation and Supercritical Fluid Extraction with CO2 as Potential Flavouring Additives for Food Applications.

Humans often respond to sensory impulses provided by aromas, and current trends have generated interest in natural sources of fragrances rather than the commonly used synthetic additives. For the first time, the resulting aroma of a selected culture of Thymus mastichina L. was studied as a potential food ingredient. In this context, dried (DR) and fresh (FR) samples were submitted to carbon dioxide (CO2) supercritical extraction (SFE) and hydrodistillation (HD) methods. The extracts were characterised according to their volatile composition by GC-MS, cytotoxicity against a non-tumour cell culture, and sensory attributes (odour threshold and olfactive descriptors). The most abundant aromas were quantified, and the analysis performed by GC-MS revealed an abundance of terpenoids such as thymol chemotype, followed by the precursors α-terpinene and p-cymene. DR and FR extracts (EX) obtained from SFE-CO2 show the highest content of thymol, achieving 52.7% and 72.5% of the isolated volatile fraction. The DR essential oil (EO) contained the highest amount of terpenoids, but it was also the most cytotoxic extract. In contrast, SFE-CO2 products showed the lowest cytotoxic potential. Regarding FR-OE, it had the lowest extraction yield and composition in aroma volatiles. Additionally, all samples were described as having green, fresh and floral sensory notes, with no significant statistical differences regarding the odour detection threshold (ODT) values. Finally, FR-EX of T. mastichina obtained by SFE-CO2 presented the most promising results regarding food application.

Formulation and Optimization of Nanoemulsions Using the Natural Surfactant Saponin from Quillaja Bark.

Replacing synthetic surfactants by natural alternatives when formulating nanoemulsions has gained attention as a sustainable approach. In this context, nanoemulsions based on sweet almond oil and stabilized by saponin from Quillaja bark with glycerol as cosurfactant were prepared by the high-pressure homogenization method. The effects of oil/water (O/W) ratio, total surfactant amount, and saponin/glycerol ratio on their stability were analyzed. The formation and stabilization of the oil-in-water nanoemulsions were analyzed through the evaluation of stability over time, pH, zeta potential, and particle size distribution analysis. Moreover, a design of experiments was performed to assess the most suitable composition based on particle size and stability parameters. The prepared nanoemulsions are, in general, highly stable over time, showing zeta potential values lower than -40 mV, a slight acid behavior due to the character of the components, and particle size (in volume) in the range of 1.1 to 4.3 µm. Response surface methodology revealed that formulations using an O/W ratio of 10/90 and 1.5 wt% surfactant resulted in lower particle sizes and zeta potential, presenting higher stability. The use of glycerol did not positively affect the formulations, which reinforces the suitability of preparing highly stable nanoemulsions based on natural surfactants such as saponins.

Antiangiogenic compounds: well-established drugs versus emerging natural molecules.

Angiogenesis is the natural and physiologic process of growing blood vessels from pre-existing ones. Pathological angiogenesis occurs when the precise balance of all the molecular pathways that regulate angiogenesis is disrupted, and this process is a critical step in many diseases, including cancer. A limited number of antiangiogenic synthetic drugs have been developed. However, due to toxicity and side effects issues, the search for alternative to existing drugs is ongoing. In this sense, natural molecules obtained from plants or macrofungi, have demonstrated extraordinary potential in the treatment of angiogenesis-related pathologies, specially taking into consideration its absence or very low toxicity, when compared to synthetic drugs. Using natural compounds as potential angiogenesis modulators is thus a promising field of research, supporting the creation of novel therapies able to reduce the use of drugs and associated side effects. In this review, the current status of antiangiogenic drugs and the wide variety of natural extracts and molecules with antiangiogenic capacities, as well as the angiogenesis molecular pathways and therapeutic targets, are presented. Finally, the challenges that need to be overcome in order to increase the use of natural compounds for clinical purposes are discussed.

Continuous flow photo-Fenton treatment of ciprofloxacin in aqueous solutions using homogeneous and magnetically recoverable catalysts.

The degradation of ciprofloxacin was studied in aqueous solutions by using a continuous flow homogeneous photo-Fenton process under simulated solar light. The effect of different operating conditions on the degradation of ciprofloxacin was investigated by changing the hydrogen peroxide (0-2.50 mM) and iron(II) sulphate (0-10 mg Fe L(-1)) concentrations, as well as the pH (2.8-10), irradiance (0-750 W m(-2)) and residence time (0.13-3.4 min) of the process. As expected, the highest catalytic activity in steady state conditions was achieved at acidic pH (2.8), namely 85 % of ciprofloxacin conversion, when maintaining the other variables constant (i.e. 2.0 mg L(-1) of iron(II), 2.50 mM of hydrogen peroxide, 1.8 min of residence time and 500 W m(-2) of irradiance). Additionally, magnetite magnetic nanoparticles (ca. 20 nm of average particle size) were synthesized, characterized and tested as a possible catalyst for this reaction. In this case, the highest catalytic activity was achieved at natural pH, namely a 55 % average conversion of ciprofloxacin in 1.8 min of residence time and under 500 W m(-2). Some of the photocatalytic activity was attributed to Fe(2+) leaching from the magnetic nanoparticles to the solution.

A highly reproducible continuous process for hydroxyapatite nanoparticles synthesis.

This work presents a continuous process for producing hydroxyapatite nanoparticles (NanoXIM) in a network reactor, NETmix, fed by a calcium solution, a phosphorus solution and an alkaline solution. Hydroxyapatite is considered a biomaterial, used as: food additives and nutritional supplements; bone graft for bone replacement, growth and repair; biocements and coating of metallic implant. Some of the most recent applications include their use in cosmetics, toothpaste and in esthetical treatments for diminishing wrinkles by stimulating conjunctive tissue formation. The proposed process enables the micromixing control, which is essential to form nanometric structures, but it is also a determining factor in the crystals purity, crystallinity and morphology. The reactants distribution scheme at the inlet of the reactor and along the reactor, performed continuously or varying in time, is also a crucial factor to programme the properties of reactant media along the reactor, such as the pH, the supersaturation degree, the Ca/P molar ratio, and the temperature. The calcium phosphate nanoparticles suspension that exits the reactor is submitted to further aging, separation, drying, sintering and milling processes.