Moringa oleifera L. screening: SFE-CO2 optimisation and chemical composition of seed, leaf, and root extracts as potential cosmetic ingredients

Moringa oleifera L. tree (Mo) has emerged as a rich alternative source of bioactive compounds to design cosmetic formulations. Supercritical carbon dioxide fluid extraction (SFE-CO2) was successfully applied on the screening of Mo seed, leaf, and root extracts. The extraction yield was evaluated by response surface methodology (RSM), for pressure and temperature ranges of 117–273 bar and 41–60 C, respectively, using a design of experiments (DOE). The pressure significantly affected the results (a = 0.05), with the highest extraction efficiency obtained at conditions above 195 bar. The extracts’ composition, evaluated by gas chromatography-mass spectrometer (GC-MS), revealed an increasing correlation between the pressure, total extract solubility, and mass of extract at a constant temperature, due to the higher extraction yield. Seed extracts presented more than 80% of oleic acid in relative composition (8.04 mgcompound gplantpart -1). Leaf extracts performed well for the obtainment of linolenic acid (>20%; 3.10 mg g-1), nonacosane (>22%; 0.46 mg g-1), and -tocopherol (>20%; 0.21 mg g-1). Mo root resulted in higher relative composition for sterol molecules, despite its very low affinity with CO2. The most promising bioactive compounds, oleic acid and -tocopherol, were more abundant when operating at 250 bar at 45 C and 195 bar at 55 C, for Mo seed and leaf SFE-CO2 extracts, respectively.This work was financially supported by LA/P/0045/2020 (ALiCE), UIDB/50020/2020 and UIDP/50020/2020 (LSRE-LCM), UIDB/00690/2020 and UIDP/00690/2020 (CIMO) and LA/P/0007/2021 (SusTEC), funded by national funds through the Fundação para a Ciência e Tecnologia FCT/MCTES (PIDDAC). Júlia Cristiê Kessler acknowledges her PhD scholarship (ref. 2020.06656.BD) from FCT.info:eu-repo/semantics/publishedVersio

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.This work was funded by the European Regional Development Fund (ERDF) through the Regional Operational Program North 2020, within the scope of Project Mobilizador Norte-01-0247-FEDER-024479: ValorNatural ®. This work was also supported by LA/P/0045/2020 (ALiCE), UIDB/50020/2020 and UIDP/50020/2020 (LSRE-LCM), and UIDB/ 00690/2020 (CIMO) funded by national funds through FCT/MCTES (PIDDAC). L. Barros and R. Calhelha also thank the national funding by FCT, P.I. through the institutional scientific employment and individual program-contract, and Júlia Cristiˆe Kessler acknowledges her Ph.D scholarship (ref. 2020.06656.BD) by FCT.info:eu-repo/semantics/publishedVersio

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 -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.This research was funded by the European Regional Development Fund (ERDF) through the Regional Operational Program North 2020, within the scope of Project Mobilizador Norte- 01-0247-FEDER-024479: ValorNatural. This work was financially supported by: LSRELCM Base- UIDB/50020/2020 and Programmatic- UIDP/50020/2020 and CIMO UIDB/00690/2020, funded by national funds through FCT/MCTES (PIDDAC). L. Barros also thanks the national funding by FCT, P.I. through the institutional scientific employment and individual program contract, and Júlia Cristiê Kessler and Filipa Mandim acknowledges their Ph.D. scholarships by Fundação para a Ciência e a Tecnologia (FCT) (2020.06656.BD and SFRH/BD/146614/2019, respectively).info:eu-repo/semantics/publishedVersio

Rheological behavior of a silver aqueous nanofluid stabilized with aminosilane-based surfactant under confined flow

\u3cp\u3eThe rheological behavior of an aqueous suspension of silver nanoparticles stabilized with aminosilane-based surfactant flowing under confnement was investigated. Three stability levels were defned based on the zeta potential: high (41.73 mV, pH 4.3), medium (10.44 mV, pH 7.4), and low (0.74 mV, pH 8.6). Furthermore, the preliminary investigation showed that the surface charge remained positive, and the formation of agglomerates was not observed. Due to the particle coating and the ionization of the amino groups of the surfactant an electrosteric stabilization was evidenced. Shear rates ranging from 50 to 1000 s-1 and shear stresses between 0.02 and 0.2 Pa, at the temperatures of 15, 25 and 35 °C, were evaluated with the nanofluid flowing in microchannels with a gap of 100, 300 and 500 μm. A trend to dilatant behavior was observed at high shear rate and a slit size of 500 μm, while Newtonian behavior was predominant at lower slit sizes. A reduction of 47.3% was noticed at 25 °C with the variation in the slit size from 500 to 300 μm. Furthermore, the viscosity of the nanofluid decreased as much as 60% when the slit size was reduced from 500 to 100 μm.\u3c/p\u3

Corrigendum to “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 authors regret the inconvenience caused but found an error in the text of section 2.5.3 - “Sensory evaluation of the aroma of bread” of the article. It should read “Four concentrations of R. officinalis extract were used: 0.0, 0.5, 1.0 and 2.0 μL/100 g of bread.” instead of “Four concentrations of R. officinalis extract were used: 0.0, 0.5, 1.0 and 2.0 g/100 g of bread.” The authors would like to apologise for any inconvenience caused