Protective effect of hydroxytyrosol and rosemary extract in a comparative study of the oxidative stability of Echium oil

Study of the oxidative stability via Oxitest and Rancimat of phenolic-rich olive oils obtained by a sequential process of dehydration, expeller and supercritical CO2 extractions

The oxidative stability of olive oils extracted by different methods, i.e. conventional 2-phase extraction (cOO), and sequential extraction by expeller press (eOO) and supercritical CO2 (SCOO), was determined by using two accelerated oxidation methods, Oxitest and Rancimat, in the temperature range 90-160°C. The kinetic analyses carried out provided Arrhenius activation energies, enthalpies, entropies and Gibb's free energies of activation, temperature coefficients, Q10 factors, and the oxidative stability indexes at 20°C (OSI20) for the different oils. A good correlation between the two techniques was obtained (r2 = 0.996). Oxitest showed, however, shorter induction times and less sample quantity (1 g vs. 3 g in Rancimat) requirements, suggesting that it could be a good and faster alternative to Rancimat for the evaluation of the oil oxidative stability. cOO showed OSI20 values of 38.5 and 42.5 months, by the Rancimat and Oxitest methods, respectively. Furthermore, eOO and SCOO showed OSI20 values of 43.3 and 138.6 months by Rancimat and 67 and 142 months by the Oxitest method, respectively. The strong correlation found between the phenolic content of the oils and their OSI20 values confirms that a higher oil phenolic content would improve the oxidative stability of the oils.

The whitening efficacy of a compound formula examined using an ultraviolet-induced skin melanization model

BACKGROUND

In Eastern culture, a fair complexion is the standard of beauty, leading to appearance-related distress among women with darker skin or facial pigmentation. Women seek whitening cosmetics to enhance their skin tone or correct their pigmentation, but their safety and effectiveness are paramount factors to consider. In this study, we evaluated the safety and whitening effects of a compound formula denoted as TEST comprising astaxanthin, nicotinamide, arbutin, and tranexamic acid.

METHODS

Primary skin irritation and skin-whitening efficacy were examined. Three qualified melanization areas were treated with TEST, 7% ascorbic acid, or a blank. Skin color, the individual type angle (ITA°), and the melanin index (MI) were compared among treatment areas.

RESULTS

TEST did not induce a skin response and exhibited a significantly higher ITA° than the blank, while no significant difference was observed with that of 7% ascorbic acid. Furthermore, the MI of TEST was significantly reduced posttreatment.

CONCLUSIONS

TEST could be integrated into spot-fading and skin-whitening cosmeceuticals or functional cosmetics.

Shelf Life Enhancement of Structured Lipids Rich in Omega-3 Fatty Acids Using Rosemary Extract: A Sustainable Approach

This study investigates the efficacy of rosemary extract (RE) in stabilizing structured lipids (SL) developed using perilla seed oil (PSO) and palmolein (PO) under accelerated storage conditions. The oil samples, comprising PSO, Blend, and SL formulations with and without RE (1500 ppm) and BHT (200 ppm), were studied for their storage stability during a 30 day storage period at 65 °C, with the analysis carried out at 6 day intervals. Oxidative properties were comprehensively assessed, including both physical attributes (color, viscosity, and refractive index) and chemical parameters (peroxide value, free fatty acid (FFA), p-anisidine value, TOTOX value, conjugated dienes, and trienes). The results demonstrated that RE-enriched oil samples exhibited significantly higher oxidative stability (p < 0.05) compared to the control group. SL added with 1500 ppm of RE exhibited notable enhancements in quality parameters, showcasing reductions in FFA, TOTOX value, conjugated diene, and triene value by 44.01%, 35.42, 39.03, and 47.36, respectively, when compared to SL without any antioxidant. The RE at 1500 ppm concentration showed a similar effect as the synthetic antioxidant BHT at 200 ppm. Also, the RE demonstrated potent inhibition of the oxidation of polyunsaturated fatty acids, thereby contributing to the improved oxidative stability of the SLs. Furthermore, SL with RE also exhibited reduced degradation of the tocopherol content and total phenolic content during the storage period. Principal component analysis demonstrated that SL and blend followed similar oxidative characteristics as they fell within the same quadrant. These findings underscore RE as a potent source of antioxidants capable of scavenging free radicals and enhancing the oxidative stability of omega-3 fatty acid-rich SLs.

Improved accelerated stability of starch-chia oil fatty acid inclusion complexes formed under mild reaction conditions

The starch inclusion complexation of sensitive compounds requires the use of conditions that minimize their degradation. This research work is aimed at investigating the effect of an alkaline complexation method employing mild reaction conditions on the physicochemical properties and accelerated stability of inclusion complexes of high amylose corn starch with omega-3 and omega-6 fatty acids. Hydrolyzed chia seed oil, rich in α-linolenic and linoleic fatty acids, was used as guest material and was incorporated at two ratios (10 and 20 % w/w hydrolysate/starch). Under the reaction conditions assessed, it were successfully formed V-type inclusion complexes with a high content of omega-3 and omega-6 (3.9-6 %). The initial hydrolysate concentration did not have a significant effect on the structural (crystallinity, short-range order) and thermal (dissociation temperature, melting enthalpy) properties. The method studied allowed the formation of complexes with an enhanced accelerated oxidative stability, compared to those formed using thermal treatment. The complexes formed using mild conditions with 20 % hydrolysate content had the highest oxidative stability, showing an omega-3 and omega-6 retention >90 % after 6 h of storage at 90 °C, an enhanced stability under thermogravimetric analysis, and flattened Rancimat curves, suggesting an appropriate preliminary behavior as potential carriers of bioactive fatty acids.

Preliminary study of physicochemical, thermal, rheological, and interfacial properties of quinoa oil

Background: The growing popularity of nutrient-rich foods, among which is quinoa, is due to the increasing demand for healthier choices. Oils and hydrolyzed proteins from these foods may help prevent various health issues. The objective of this work was to perform extraction from the endosperm of the grain from high-protein quinoa flour by physical means via a differential abrasive milling process and extracting the oil using an automatic auger extractor at 160°C, as well as characterizing extracted oil. Methods: Quinoa oil extraction and physicochemical characterization were carried out. Chemical and physical quality indexes of quinoa oil were established, and both characterizations were conducted based on international and Columbian standards. Thermal properties were evaluated by differential scanning calorimetry, and rheological and interfacial properties of the oil were evaluated using hybrid rheometers and Drop Tensiometers, respectively, to determine its potential for obtaining functional foods. Results: The result was 10.5 g of oil/ 100 g of endosperm, with a moisture content of 0.12%, insoluble impurities of 0.017%, peroxide index of 18.5 meq O 2/kg of oil, saponification index of 189.6 mg potassium hydroxide/g of oil, refractive index of 1.401, and a density of 0.9179 g/cm 3 at 20°C. Regarding contaminating metals, it presented 7 mg of iron/kg of oil, a value higher than previously established limits of 5 mg of iron/kg of oil. The oil contained 24.9% oleic acid, 55.3% linoleic acid, and 4% linolenic acid, demonstrating antioxidant capacity. Quinoa oil showed thermal properties similar to other commercial oils. Conclusions: The interfacial and rheological properties were suitable for the stabilization of emulsions, gels, and foams, which are important in various industrial applications and could facilitate the development of new products. The extracted quinoa oil presented similar characteristics to other commercial oils, which could make it a potential product for commercialization and application in different industries.

Promoting FADH2 Regeneration of Hydroxylation for High-Level Production of Hydroxytyrosol from Glycerol in Escherichia coli

Hydroxytyrosol is a natural polyphenolic compound widely used in the food and drug industries. The current commercial production of hydroxytyrosol relies mainly on plant extracts, which involve long extraction cycles and various raw materials. Microbial fermentation has potential value as an environmentally friendly and low-cost method. Here, a de novo biosynthetic pathway of hydroxytyrosol has been designed and constructed in an Escherichia coli strain with released tyrosine feedback inhibition. By introduction of hpaBC from E. coli and ARO10 and ADH6 from Saccharomyces cerevisiae, the de novo biosynthesis of hydroxytyrosol was achieved. An important finding in cofactor engineering is that the introduction of L-amino acid deaminase (LAAD) promotes not only cofactor regeneration but also metabolic flow redistribution. To further enhance the hydroxylation process, different 4-hydroxyphenylacetate 3-monooxygenase (hpaB) mutants and HpaBC proteins from different sources were screened. Finally, after optimization of the carbon source, pH, and seed medium, the optimum engineered strain produced 9.87 g/L hydroxytyrosol in a 5 L bioreactor. This represents the highest titer reported to date for de novo biosynthesis of hydroxytyrosol in microorganisms.

Determination of the Optimum Conditions for Emulsification and Encapsulation of Echium Oil by Response Surface Methodology

Echium oil (EO) contains substantial amounts of omega-3 fatty acids, which are important because of their benefits to human health. However, they are prone to oxidation. The aim of this study was to obtain the optimum conditions of microencapsulation of EO using spray drying by applying the response surface methodology (RSM). Central composite circumscribed design (CCC) was employed with a ratio of maltodextrin (MD):EmCap modified starch (MS) (80-90%, w/w), oil concentration (15-25%, w/w), and homogenization speed (5-15 × 103 rpm) as independent variables affecting droplet size (μm) and viscosity (Pa·s), which were chosen as responses for the emulsification process. The results revealed that the emulsion conditions containing MD:MS (89.7%:10.3%, w/w), oil concentration of (16.0%), and homogenization speed at (14.8 × 103 rpm) were found to be the optimum conditions. Furthermore, for encapsulation, CCC was employed with inlet temperature of 140-180 °C, air flow of 20-30%, and pump rates of 15-25% as independent variables. Total yield (%) and encapsulation efficiency (%) were chosen as responses for the encapsulation process. On the other hand, optimum conditions for encapsulation were as follows: inlet temperature of 140 °C, airflow rate of (30%) 0.439 m3/h, pump rate of (15%) 4.5 mL/min with respect to selected responses.

Antioxidant properties of lipid concomitants in edible oils: A review

Edible oils are indispensable for human life, providing energy and necessary fatty acids. Nevertheless, they are vulnerable to oxidation via a number of different mechanisms. Essential nutrients deteriorate as well as toxic substances are produced when edible oils are oxidized; thus, they should be retarded wherever possible. Lipid concomitants have a strong antioxidant capacity and are a large class of biologically active chemical substances in edible oils. They have shown remarkable antioxidant properties and were documented to improve the quality of edible oils in varied ways. An overview of the antioxidant properties of the polar, non-polar, and amphiphilic lipid concomitants present in edible oils is provided in this review. Interactions among various lipid concomitants and the probable mechanisms are also elucidated. This review may provide a theoretical basis and practical reference for food industry practitioners and researchers to understand the underlying cause of variations in the quality of edible oils.

Addition of Olive Leaf Extract to a Mixture of Algae and Extra Virgin Olive Oils Decreases Fatty Acid Oxidation and Synergically Attenuates Age-Induced Hypertension, Sarcopenia and Insulin Resistance in Rats

Olive-derived products, such as virgin olive oil (EVOO) and/or olive leaf extracts (OLE), exert anti-inflammatory, insulin-sensitizing and antihypertensive properties and may be useful for stabilizing omega 3 fatty acids (n-3 PUFA) due to their high content in antioxidant compounds. In this study, the addition of OLE 4:0.15 (w/w) to a mixture of algae oil (AO) rich in n-3 PUFA and EVOO (25:75, w/w) prevents peroxides formation after 12 months of storage at 30 °C. Furthermore, the treatment with the oil mixture (2.5 mL/Kg) and OLE (100 mg/Kg) to 24 month old Wistar rats for 21 days improved the lipid profile, increased the HOMA-IR and decreased the serum levels of miRNAs 21 and 146a. Treatment with this new nutraceutical also prevented age-induced insulin resistance in the liver, gastrocnemius and visceral adipose tissue by decreasing the mRNA levels of inflammatory and oxidative stress markers. Oil mixture + OLE also attenuated the age-induced alterations in vascular function and prevented muscle loss by decreasing the expression of sarcopenia-related markers. In conclusion, treatment with a new nutraceutical based on a mixture of EVOO, AO and OLE is a useful strategy for improving the stability of n-3 PUFA in the final product and to attenuate the cardiometabolic and muscular disorders associated with aging.

Combination of natural strategies to improve the oxidative stability of echium seed oil

Echium seed oil is an alternative source of omega 3 fatty acids but it is highly susceptible to oxidation. A combination of three natural strategies was proposed in this study aiming to improve the oxidative stability of echium oil obtained by pressing (PO) or solvent extraction (PSO), kept in the storage condition for 180 days or during the consumption for 30 days. Our results showed that the reduction of temperature was sufficient to keep the oil stable during storage for both samples. During the consumption time, the best stability was achieved by adding a mixture of antioxidants, composed of sinapic (500 ppm), ascorbic (250 ppm), and citric (150 ppm) acids, and/or 20% of high oleic sunflower oil. The combined strategies promoted a 34 to 80% reduction of peroxide value and 0 to 85% reduction of malondialdehyde concentrations in the samples, showing to be a feasible and natural alternative to improve the oxidative stability of echium oil. PRACTICAL APPLICATION: Our study successfully applied an optimized combination of simple and low-cost strategies to enhance the chemical stability of echium seed oil. As the use of echium oil expands around the world, the oil industry and final consumers may benefit from our results to increase the oil shelf-life.

Olive Pomace-Derived Biomasses Fractionation through a Two-Step Extraction Based on the Use of Ultrasounds: Chemical Characteristics

Olive-derived biomass is not only a renewable bioenergy resource but also it can be a source of bioproducts, including antioxidants. In this study, the antioxidant composition of extracted olive pomace (EOP) and a new byproduct, the residual fraction from olive pit cleaning (RFOPC or residual pulp) was characterized and compared to olive leafy biomass, which have been extensively studied as a source of antioxidants and other bioactive compounds with pharmacological properties. The chemical characterization showed that these byproducts contain a high amount of extractives; in the case of EOP, it was even higher (52.9%) than in olive leaves (OL) and olive mill leaves (OML) (35.8-45.1%). Then, ultrasound-assisted extraction (UAE) was applied to recover antioxidants from the extractive fraction of these biomasses. The solubilization of antioxidants was much higher for EOP, correlating well with the extractives content and the total extraction yield. Accordingly, this also affected the phenolic richness of the extracts and the differences between all biomasses were diminished. In any case, the phenolic profile and the hydroxytyrosol cluster were different. While OL, OML, and EOP contained mainly hydroxytyrosol derivatives and flavones, RFOPC presented novel trilignols. Other compounds were also characterized, including secoiridoids, hydroxylated fatty acids, triterpenoids, among others, depending on the bioresource. Moreover, after the UAE extraction step, alkaline extraction was applied recovering a liquid and a solid fraction. While the solid fraction could of interest for further valorization as a biofuel, the liquid fraction contained proteins, sugars, and soluble lignin, which conferred antioxidant properties to these extracts, and whose content depended on the biomass and conditions applied.

Application of Hydroxytyrosol in the Functional Foods Field: From Ingredient to Dietary Supplements

Hydroxytyrosol (HT) is an amphipathic functional phenol found in the olive tree, both in its leaves and fruits, in free or bound forms, as well as in olive oil and by-products of olive oil manufacture. The European Food Safety Authority recommends regular consumption of HT due to its several beneficial effects on human health, which are closely associated to its antioxidant activity. These reasons make HT an excellent candidate for application as a functional ingredient in the design of novel food products. Patents already exist for methodologies of extraction, purification, and application of HT in supplements and food products. The present review discusses the impact of HT incorporation on food properties and its effects on consumers, based on relevant data related to the use of HT as a functional ingredient, both as a pure compound or in the form of HT-rich extracts, in various food products, namely in edible oils, beverages, bakery products, as well animal-based foods such as meat, fishery and dairy products.

Impact of a novel partial defatting technology on oxidative stability and sensory properties of peanut kernels

A novel process, 'mechanical expression preserving shape integrity', was conceived to prepare low-fat peanuts in response to health-conscious consumer demands. The main purpose of this study was to preserve the taste, aroma, and oxidative stability of the defatted product. Results generated from a central composite rotatable design showed that highest consumer sensory scores were reached at low pressures (4-6 MPa). Free fatty acid, peroxide, p-anisidine, and total oxidation values were mostly affected by water content [W] and pressure [P] with high correlation coefficients (82% < R² < 87%). Overall, lipid oxidation and flavor fade were associated with higher defatting ratios and greater physical damage. The latter plays a major role in increasing the surface area and facilitating the access of oxygen to the remaining oil, thus rendering the defatted product more prone to oxidation. However, oxidation was reduced significantly using a Response Surface Methodology to optimize conditions ([W] 12.2 ± 0.6%d.b., [P] 6 ± 0.3 MPa and time [t] 18.2 ± 0.6 min).

Carnosol inhibits inflammasome activation by directly targeting HSP90 to treat inflammasome-mediated diseases

Aberrant activation of inflammasomes, a group of protein complexes, is pathogenic in a variety of metabolic and inflammation-related diseases. Here, we report that carnosol inhibits NLRP3 inflammasome activation by directly targeting heat-shock protein 90 (HSP90), which is essential for NLRP3 inflammasome activity, thereby treating inflammasome-mediated diseases. Our data demonstrate that carnosol inhibits NLRP3 inflammasome activation in primary mouse bone marrow-derived macrophages (BMDMs), THP-1 cells and human peripheral blood mononuclear cells (hPBMCs). Mechanistically, carnosol inhibits inflammasome activation by binding to HSP90 and then inhibiting its ATPase activity. In vivo, our results show that carnosol has remarkable therapeutic effects in mouse models of NLRP3 inflammasome-mediated diseases, including endotoxemia and nonalcoholic steatohepatitis (NASH). Our data also suggest that intraperitoneal administration of carnosol (120 mg/kg) once daily for two weeks is well tolerated in mice. Thus, our study reveals the inhibitory effect of carnosol on inflammasome activation and demonstrates that carnosol is a safe and effective candidate for the treatment of inflammasome-mediated diseases.

Antioxidant properties of two novel lipophilic derivatives of hydroxytyrosol

Two novel lipophilic derivatives of the natural olive oil phenol, hydroxytyrosol (HT), were synthesized using 3,4-dihydroxyphenylacetic acid as starting material. Their antioxidant activities and kinetics compared to HT and TBHQ were assessed by Rancimat, Schaal Oven, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and deep-frying methods. All experiments, including kinetic data analysis based on the Arrhenius equation, utilized in assessing antioxidant activity except the DPPH assay revealed that the new lipophilic HT derivatives exhibited much stronger antioxidant activity than hydroxytyrosol. Tert-butylhydroquinone exhibited stronger antioxidant activity in bulk oil at 65 °C than the new HT derivatives, but showed much lower activity at higher temperatures (>110 °C). This demonstrates that the introduction of bulky alkyl moiety to the ortho-diphenolic structure of HT increased its antioxidant activity. It can be concluded that the new lipophilic HT derivatives satisfy industrial demands for bioactive compounds with strong antioxidant potential at high temperatures.

Comparison of in vitro antioxidative activities of crude methanolic extracts of three species of Passiflora from greenhouse using DPPH, ABTS and FRAP methods

Introduction:. It is well documented that many species from Passifloraceae family can provide edible and nutritious fruits while the leaves of cultivated plants are renewable and waste material. This biomass may be further used in various sectors, especially as a bioactive food additive and as source of innovative pharmaceuticals, cosmetics or feed additives. The biomaterials and green chemistry are new sectors bioeconomy according to the high-level horizontal strategies and bio-based industries in Europe. In recent years, attention has been paid to the biological activity and phytochemical profiles of extracts from different species of Passiflora. However, there is little comparative studies using the same procedures and techniques in the same laboratory conditions for study of plant material obtained from the similar greenhouse conditions.

Objective: This study was focused on the examination of antioxidative activities of low concentrations of crude extracts from leaves of Passiflora incarnata L., Passiflora caerulea L., and Passiflora alata Curtis.

Methods: The activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging and ferric reducing antioxidant power (FRAP) methods. Results of study were supported by estimation of chemical composition with secondary metabolites profiling in extracts which were carried out previously for the same extracts from three Passiflora species. One-way ANOVA analysis revealed significant differences in the antioxidant activity of various concentrations of the extracts using the DPPH and ABTS radical models, and FRAP method.

Results: Measurement of antioxidant capacity (expressed as trolox equivalent, TE) showed that the most active was extract of P. caerulea > P. alata > P. incarnata. Phytochemical analysis for extracts of P. caerulea and P. incarnata showed greater similarities in metabolites content than P. alata. However, comparative statistical analysis of antioxidant activity showed that despite this phytochemical similarities, extract from P. alata leaves had higher activities than extract from leaves P. incarnata. Antioxidant effect of extract from P. alata can be explain by terpenoids presented in this extract. In this work, there have been discussed activities against Acanthamoeba castellanii strain, antibacterial and antifungal activities against selected clinical microorganisms (Enterococcus faecalis, Escherichia coli, Staphylococcus aureus, and Candida albicans, Micro-sporum gypseum), and anti-leukemic activities tested in human acute lymphoblastic leukemia cell lines for this extracts, which have been described in previous authors’ publications.

Conclusion: Our current and previous studies showed that the same crude extracts from leaves of P. alata, P. caerulea, P. incarnata exerted not only antioxidant potential in vitro but also few interesting properties such as antibacterial, antifungal, amoebostatic, amoebicidal activities, which indicate the possibility of using these extracts in both a healthy diet and natural cosmetics. Leaves of this species may become an interesting source of biomaterials which can exert health-promoting effects.