Use of the jabuticaba (Myrciaria cauliflora) depulping residue to produce a natural pigment powder with functional properties

The aim of this study was to produce a natural pigment powder with functional properties. To optimise the spray-drying process, a central composite design with 17 treatments was used, in which the independent variables were the inlet drying air temperature (138–202 °C), the feed flow rate (20–67 mL/min), and the concentration of the carrier (maltodextrin, 100–300 g/kg of extract). The dependent variables were the moisture content, hygroscopicity, and anthocyanin retention. The samples were analysed by: anthocyanin and phenolic content; antioxidant properties based on the ORAC and DPPH assays; antimicrobial activity against Staphylococcus aureus, Listeria monocytogenes, Salmonella enteritidis, and Escherichia coli; and inhibitory activity against arginase, an enzyme produced by Leishmania amazonensis. The experimental design was not significant or predictive in the ranges studied. The selected samples contained high concentrations of anthocyanins and phenolics, and high antioxidant capacities. In addition, they exhibited antimicrobial activity against three of the four microorganisms tested, and some of the samples also exhibited a bactericidal effect. Moreover, the powders exerted inhibitory activity (64–69%) against arginase. The results obtained in this study suggest that the jabuticaba depulping residue could be used to produce a natural pigment with functional properties.     

Encapsulation of Noble Metal Nanoparticles through Seeded Emulsion Polymerization as Highly Stable Plasmonic Systems

The implementation of plasmonic nanoparticles in vivo remains hindered by important limitations such as biocompatibility, solubility in biological fluids, and physiological stability. A general and versatile protocol is presented, based on seeded emulsion polymerization, for the controlled encapsulation of gold and silver nanoparticles. This procedure enables the encapsulation of single nanoparticles as well as nanoparticle clusters inside a protecting polymer shell. Specifically, the efficient coating of nanoparticles of both metals is demonstrated, with final dimensions ranging between 50 and 200 nm, i.e., sizes of interest for bio‐applications. Such hybrid nanocomposites display extraordinary stability in high ionic strength and oxidizing environments, along with high cellular uptake, and low cytotoxicity. Overall, the prepared nanostructures are promising candidates for plasmonic applications under biologically relevant conditions.     

Development of reduced saturated fat cookie fillings using multicomponent oleogels

Cookie fillings are typically composed of sugar (60%–80%) and fat (20%–40%). The fat in these fillings is known as shortening, which currently has high levels of saturated fatty acids (SFA) and, in some cases, trans fatty acids (TFA). This makes the nutritional profile of this product a reason for concern, especially considering that the target audience for cookies is children. This study thus aimed to replace the commercial shortening in these fillings with oleogels made of soybean oil (SB) and high oleic sunflower oil (SF) structured with candelilla wax (CLX), monoglycerides (MG), and hard fat (HF), in different concentrations ranging from 5%–10% of the total structuring content. The complete replacement of shortening with oleogel reduced the amount of TFA by 100% and the amount of SFA by 50%–80%. The quantities of MG and HF greatly influenced the structuring of the product because the higher the concentrations (≥3%), the better the formation of the structured network, with good aeration, greater hardness, and less oil loss, compared with the standard with shortening. The samples that achieved physical properties similar to those of the control sample were samples 3:3:3 and 1:4:5 (CLX:MG:HF). These showed similar oil loss at T0 (~4.5%), and microstructure before and after temperature oscillations and closer consistency (~400 gF/cm²) and adhesiveness (50 gF. s) to the RP (800 gF/cm² and 75 gF. s). Although MG and HF are not good structuring elements alone as the CLX, they formed a network that is connected by hydrogen bonds with the sugar molecules that were resistant to stirring and thermal changes, which makes this system a potential replacement for shortenings in cookie fillings application.     

Gamma radiation effects on peanut skin antioxidants

Peanut skin, which is removed in the peanut blanching process, is rich in bioactive compounds with antioxidant properties. The aims of this study were to measure bioactive compounds in peanut skins and evaluate the effect of gamma radiation on their antioxidant activity. Peanut skin samples were treated with 0.0, 5.0, 7.5, or 10.0 kGy gamma rays. Total phenolics, condensed tannins, total flavonoids, and antioxidant activity were evaluated. Extracts obtained from the peanut skins were added to refined-bleached-deodorized (RBD) soybean oil. The oxidative stability of the oil samples was determined using the Oil Stability Index method and compared to a control and synthetic antioxidants (100 mg/kg BHT and 200 mg/kg TBHQ). Gamma radiation changed total phenolic content, total condensed tannins, total flavonoid content, and the antioxidant activity. All extracts, gamma irradiated or not, presented increasing induction period (h), measured by the Oil Stability Index method, when compared with the control. Antioxidant activity of the peanut skins was higher than BHT. The present study confirmed that gamma radiation did not affect the peanut skin extracts' antioxidative properties when added to soybean oil.     

Sensory and Technological Evaluation of Margarines With Reduced Saturated Fatty Acid Contents Using Oleogel Technology

Margarines and spreads contribute greatly to the intake of saturated and trans fats in the diet. Therefore, the objective of this work was to produce margarines using the oleogel technology and to verify the physical, thermal, oxidative, and sensorial properties of this product during six months of shelf life, comparing it with commercial margarine. When compared with commercial margarine, the oleogel margarine showed similar color results. Due to the different structural shape, the results of microstructure and the melting curve were differentiated, but this indicated a structure more resistant to temperature oscillations and an overall softer product. However, the sensorial difference between the samples was easily detected by the consumers, mainly with respect to the parameters of taste, texture, and overall impression. It was concluded that it is possible to produce margarines using the oleogel technology, which display good physical properties, similar shelf life, and improved nutritional characteristics.     

Small Extracellular Vesicles from Hypoxic Triple-Negative Breast Cancer Cells Induce Oxygen-Dependent Cell Invasion

Hypoxia, a condition of low oxygenation frequently found in triple-negative breast tumors (TNBC), promotes extracellular vesicle (EV) secretion and favors cell invasion, a complex process in which cell morphology is altered, dynamic focal adhesion spots are created, and ECM is remodeled. Here, we investigated the invasive properties triggered by TNBC-derived hypoxic small EV (SEVh) in vitro in cells cultured under hypoxic (1% O₂) and normoxic (20% O₂) conditions, using phenotypical and proteomic approaches. SEVh characterization demonstrated increased protein abundance and diversity over normoxic SEV (SEVn), with enrichment in pro-invasive pathways. In normoxic cells, SEVh promotes invasive behavior through pro-migratory morphology, invadopodia development, ECM degradation, and matrix metalloprotease (MMP) secretion. The proteome profiling of 20% O₂-cultured cells exposed to SEVh determined enrichment in metabolic processes and cell cycles, modulating cell health to escape apoptotic pathways. In hypoxia, SEVh was responsible for proteolytic and catabolic pathway inducement, interfering with integrin availability and gelatinase expression. Overall, our results demonstrate the importance of hypoxic signaling via SEV in tumors for the early establishment of metastasis.