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The primary cause of bottled wine sediment is tartrate crystal precipitation. To prevent this, wines undergo a stabilization process before bottling. The most commonly used method is cold stabilization, which induces the precipitation of tartrate crystals that are then removed, thereby eliminating the excess ions that cause instability in wine. Another approach to tartaric stabilization is using enological stabilizers with a colloid protective effect, which prevents the formation of tartrate crystals. The most commonly used tartaric stabilizers are sodium carboxymethylcellulose (CMC) and metatartaric acid. However, both have drawbacks: they are semi-synthetic products, and metatartaric acid degrades over time, losing its stabilizing effect. This study aims to compare the effects of cold stabilization, stabilization with CMC, and metatartaric acid on the chemical composition, particularly the volatilome, of white, rosé, and red wines. Cold stabilization significantly impacted the wine volatilome, especially in white and rosé wines, by decreasing total alcohols and increasing total esters. It also reduced the color intensity of rosé and red wines by lowering monomeric anthocyanins. In contrast, enological stabilizers had minimal impact on the wines' phenolic composition, chromatic characteristics, and volatilome. The sensory impact of cold stabilization is complex; it can potentially enhance the aroma of white and rosé wines by increasing ester VOCs and decreasing higher alcohols, but it negatively affects the color of rosé and red wines.

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A technique is proposed to detect the presence of the multipath effect in Global Navigation Satellite Signal (GNSS) signals using a convolutional neural network (CNN) as the building block. The network is trained and validated, for a wide range of C/N0 values, with a realistic dataset constituted by the synthetic noisy outputs of a 2D grid of correlators associated with different Doppler frequencies and code delays (time-domain dataset). Multipath-disturbed signals are generated in agreement with the various scenarios encompassed by the adopted multipath model. It was found that pre-processing the outputs of the correlators grid with the two-dimensional Discrete Fourier Transform (frequency-domain dataset) enables the CNN to improve the accuracy relative to the time-domain dataset. Depending on the kind of CNN outputs, two strategies can then be devised to solve the equation of navigation: either remove the disturbed signal from the equation (hard decision) or process the pseudoranges with a weighted least-squares algorithm, where the entries of the weighting matrix are computed using the analog outputs of the neural network (soft decision).

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Growing health and environmental concerns have increased demand for all-natural products, with a focus on clean labelling. Sodium nitrite is the most widely used additive in the meat industry because it imparts the typical cured flavour and colour to meat products and, most importantly, their microbiological safety. However, due to health concerns, the European Commission is proposing revised regulations to reduce nitrate and nitrite levels in meat products. As a result, the meat industry is actively seeking alternatives. This study explored the production of four cooked hams utilising nitrate-rich vegetable sources combined with two different nitrate-reducing commercial food cultures, alongside a control ham prepared with sodium nitrite (150 ppm). Microbiological, physico-chemical (pH, water activity, nitrate and nitrite concentration, lipid profile, lipid oxidation) and sensory (texture and colour profile) characterisation of the products was carried out. Challenge tests for Listeria monocytogenes, Clostridium sporogenes and Clostridium perfringens have been performed to assess the growth of pathogens, if present in the products. Results revealed comparable microbiological and physico-chemical profiles across ham formulations, with minor differences observed in colour parameters for sample C. The sensory analysis showed that for the pilot ham formulations A and D, there were no significant differences in consumer perception compared to the control ham. In the challenge tests, L. monocytogenes levels were similar in both control and tested hams. There were no significant differences in C. sporogenes and C. perfringens counts at any temperature or between test and control samples. These results indicate that this technology has a potential future in the cured meat sector, as regulators mandate the reduction of added synthetic chemicals and consumers seek healthier and more natural ingredients in their daily diets.

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The effects of normal (NA) and controlled atmosphere (CA) storage and postharvest treatment with 1-methylcyclopropene (1-MCP) before CA storage for 5 months on the volatilome, biochemical composition and quality of 'Golden Delicious' (GD) and 'Red Delicious' (RD) apples were studied. Apples stored under NA and CA maintained and 1-MCP treatment increased firmness in both cultivars. NA storage resulted in a decrease of glucose, sucrose and fructose levels in both cultivars. When compared to CA storage, 1-MCP treatment caused a more significant decrease in sucrose levels and an increase in glucose levels. Additionally, 1-MCP-treated apples exhibited a significant decrease in malic acid content for both cultivars. All storage conditions led to significant changes in the abundance and composition of the volatilome in both cultivars. GD and RD apples responded differently to 1-MCP treatment compared to CA storage; higher abundance of hexanoate esters and (E,E)-α-farnesene was observed in RD apples treated with 1-MCP. While 1-MCP was effective in reducing (E,E)-α-farnesene abundance in GD apples, its impact on RD apples was more limited. However, for both cultivars, all storage conditions resulted in lower levels of 2-methylbutyl acetate, butyl acetate and hexyl acetate. The effectiveness of 1-MCP is cultivar dependent, with GD showing better results than RD.

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The instability of calcium tartrate (CaT) in wines occurs when the effective concentration of ions surpasses the solubility product, leading to the formation of CaT crystals. Unlike potassium hydrogen tartrate (KHT), temperature has little effect on the rate of CaT precipitation, making cold stabilization ineffective. Additives like metatartaric acid and carboxymethylcellulose (CMC) have been used to mitigate this problem, but metatartaric acid's effectiveness is limited due to hydrolysis. Additionally, potassium polyaspartate (KPA), commonly used as a KHT stabilizer, has been reported to reduce wine stability regarding CaT instability. Therefore, exploring alternative stabilization methods is crucial. Alginic acid, permitted as a processing aid in winemaking, can be an alternative to CMC and metatartaric acid due to its strong negative charge and ability to bind calcium ions. This study aimed to assess alginic acid's efficacy as a CaT stabilizer compared to CMC and investigate the impact of KPA on CaT instability. The results showed that KPA did not increase CaT instability and even improved its stability in some wines. Alginic acid outperformed both CMC and KPA in mitigating CaT instability, possibly due to its higher zeta potential and calcium ion complexation ability. This study is the first to investigate the use of alginic acid for CaT stability in wine.

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Beginning in ancient times, human societies around the world continue to produce fermented beverages from locally available sugar sources [...].

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Fermented beverages, including wine, can accumulate high concentrations of biogenic amines (BAs), which can pose potential health risks. BAs are produced by various yeasts and lactic acid bacteria (LAB) during winemaking. LAB are the main contributors to the formation of histamine and tyramine, the most toxic and food safety relevant biogenic amines. Numerous factors, ranging from agricultural and oenological practices to sanitation conditions, can contribute to the formation of BAs in wines. Moreover, organic and biodynamic wines impose limitations on the use of common food additives employed to control the proliferation of native and spoilage microorganisms during vinification and storage. To mitigate histamine production, commercial starter cultures incapable of synthesising histamine have been effectively utilised to reduce wine histamine content. Alternative fermentative microorganisms are currently under investigation to enhance the safety, quality, and typicity of wines, including indigenous LAB, non-Saccharomyces yeasts, and BAs degrading strains. Furthermore, exploration of extracts from BAs-degrading microorganisms and their purified enzymes has been undertaken to reduce BAs levels in wines. This review highlights microbial contributors to BAs in wines, factors affecting their growth and BA production, and alternative microorganisms that can degrade or avoid BAs. The aim is to lessen reliance on additives, providing consumers with safer wine choices.

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Natural products are generally considered safe for human consumption, but this classification is often based on ethnobotanical surveys or their use in traditional medicine over a long period of time. However, edaphoclimatic factors are known to produce different chemotypes, which may affect the safety profile and bioactivities, and are not commonly considered for plants exploited as crops worldwide. Thymus carnosus Boiss., a thyme species with various health-promoting effects, has potential pharmaceutical applications, but edaphoclimatic factors were found to significantly impact its phytochemical composition. Thus, we aimed to assess the safety profile of T. carnosus extracts obtained from plants harvested in two locations over three consecutive years and to establish an association with specific components, an essential study in the search for new sources of nutraceuticals. Thus, the antiproliferative effect of an aqueous decoction (AD), hydroethanolic (HE) extracts, and major extracts' components of T. carnosus was evaluated on intestinal (Caco-2) and hepatic (HepG2) cell models, revealing effects dependent on extract type, cell line, and tested compounds. Flavonoids induced different cytotoxic patterns, which could be attributed to molecular structural differences. Flow cytometry analysis showed apoptosis and necrosis induction, mediated by the modulation of intracellular reactive oxygen species and mitochondrial membrane potential, effects that were dependent on the cell line and phytochemical composition and on the synergism between extracts components, rather than on the activity of an isolated compound. While ursolic acid was the component with the strongest impact on the difference between extraction methods, flavonoids assumed a pivotal role in the response of different cell lines to the extracts. We report for the first time, for Thymus spp. extracts, that variations in the phytochemical composition clearly influence the cellular response, thus highlighting the need for extract standardization for medicinal applications.

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This study assessed the microbiological quality and safety of mozzarella during various production stages in northern Tocantins, Brazil, by identifying critical biological points in the industrial environment within a tropical climatic region. Batches of mozzarella were evaluated, from raw milk to primary packaging, with a shelf life of 120 d at 4°C. Indicator microorganisms were quantified, and through microbiological and biomolecular approaches, Salmonella spp. and Listeria monocytogenes were identified. In addition, the toxigenic potential of coagulase-positive staphylococci (CPS) was characterized. Results indicated that the raw milk used for mozzarella production had low microbiological quality; pasteurization of raw milk effectively eliminated all identified pathogens and reduced microbiological counts (p > 0.05). An increase in bacterial counts (>2 log colony-forming unit [CFU]/g) and recontamination with Salmonella spp. and CPS, which potentially produce staphylococcal enterotoxin B, were observed during milk coagulation and curd draining. Stretching of the fermented curd reduced the enterobacteria, total coliforms, and Escherichia coli median values by 2.56, 2.64, and 2.3 log CFU/mL, respectively. Similarly, brining the pieces by immersion reduced the quantity of enterobacteria and total coliforms by 2.3 and 1.6 log CFU/mL, respectively. Of interest, in the freshly finished product, Salmonella spp. was present but L. monocytogenes was absent; however, after the shelf-life period, L. monocytogenes was present but Salmonella spp. was absent. Considering the environmental conditions that can promote the multiplication and preservation of pathogens and spoilage of dairy products in tropical climates, it is necessary to review operational hygiene procedures, particularly in milk coagulation vats and fermentation tables. This will ensure the production of high-quality mozzarella cheese with a reduced consumption risk.

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Red berries have gained popularity as functional and nutritious food due to their health benefits, leading to increased consumer demand and higher production, totaling over 11,000 ktons for strawberries, raspberries, and blueberries combined in 2021. Nutritionally, strawberries, raspberries, and blueberries present high levels of vitamin C (9.7-58.8 mg/100 g dry weight [dw]), folates (6-24 µg/100 g dw), and minerals (96-228 mg/100 g dw). Due to their perishable nature, producers have utilized alcoholic fermentation to extend their shelf life, not only increasing the lifespan of red berries but also attracting consumers through the production of novel beverages. Strawberry, blueberry, and raspberry wines possess low alcohol (5.5-11.1% v/v), high acidity (3.2-17.6 g/L), and interesting bioactive molecules such as phenolic compounds, carotenoids, polysaccharides, and melatonin. Distillation holds tremendous potential for reducing food waste by creating red berry spirits of exceptional quality. Although research on red berry spirits is still in the early stages, future studies should focus on their production and characterization. By incorporating these factors, the production chain would become more sustainable, profitable, and efficient by reducing food waste, capitalizing on consumer acceptance, and leveraging the natural health-promoting characteristics of these products. Therefore, this review aims to provide a comprehensive overview of the characteristics of strawberry, blueberry, and red raspberry in berries, wines, and spirits, with a focus on their chemical composition and production methods.

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This study demonstrated the feasibility of fermenting and distilling low-commercial-value red fruits such as red raspberries, blueberries, and strawberries to produce high-value red fruit spirits. The fermentation process was efficient, with all red berry wines achieving a notable ethanol conversion yield (46.33 to 66.31%), without the need for nutrient supplementation or fruit juice solid separation, which showed no significant effect on the quality of the final product. Small-scale copper Charentais alembic distillation of the fermented red fruit juices resulted in fruit spirits equivalent to 1%, 7%, and 2% of the initial volume for red raspberries, blueberries, and strawberries, respectively. Except for the blueberry spirit, which had a lower volatile compound concentration (79.4 g/hL, absolute alcohol), all the produced red fruit spirits complied with legislation, including ethanol (37.9-40.2% v/v) and methanol (22.8-877.9 g/hL, absolute alcohol) concentrations and exhibited favorable aromatic profiles. The findings highlight that fermentation and distillation are straightforward, consistent, and reproducible methods, enabling the production of high-quality red fruit spirits from economically viable red fruit sources. This presents a significant opportunity in the spirits market, offering versatile applications as low-alcohol options, base spirits, or, with re-distillation, high-alcohol spirits.

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Food intake is a basic need to sustain life, but foodborne pathogens and food-related xenobiotics are also the main health concerns regarding intestinal barrier homeostasis. With a predominant role in the well-being of the entire human body, intestinal barrier homeostasis is strictly regulated by epithelial and immune cells. These cells are also the main intervenients in oxidative stress and inflammation-related diseases in the intestinal tract, triggered, for example, by genetic/epigenetic factors, food additives, pesticides, drugs, pathogens, and their metabolites. Nevertheless, the human diet can also be seen as a solution for the problem, mainly via the inclusion of functional foods or nutraceuticals that may act as antioxidant/anti-inflammatory agents to prevent and mitigate acute and chronic oxidative damage and inflammation. A literature analysis of recent advances in this topic highlights the significant role of Nrf2 (nuclear factor erythroid 2-related factor 2) and NF-kB (nuclear factor kappa-light-chain-enhancer of activated B cells) pathways in these biological processes, with many natural products and phytochemicals targeting endogenous antioxidant systems and cytokine production and balance. In this review, we summarized and discussed studies using in vitro and in vivo models of the intestinal tract used to reproduce oxidative damage and inflammatory events, as well as the role of natural products as modulators of Nrf2 and NK-kB pathways.

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BACKGROUND: The apple (Malus domestica Borkh.) plays an important role in the trendy market of dried snacks because of its exceptional flavor and texture. In addition to the health benefits, there is also a general disposition to consume organic and do-it-yourself products. RESULTS: Three different drying temperatures, 65, 75, and 85 °C, were tested using a commercial ventilated drying oven in 'Royal Gala' and 'Golden Delicious' cultivars. Physical changes, including texture, color, shrinkage ratio, and microstructure, were evaluated for the temperatures and cultivars considered. Based on the results, particularly in terms of shrinkage, hardness, and crispiness, a drying temperature of 75 °C was selected to perform texture profile analyses throughout the drying period. Storability conditions were evaluated to determine the best moment to maintain the physical properties of the dried snacks during storage. Considered the more important property related to consumer preferences, crispiness was followed with puncture tests. CONCLUSION: The storage of apple chips, dried at the various temperatures, that must be performed in 5-10 min after removing from the drying oven, was assessed over the course of a month. Both the drying process and the subsequent storage proved effective in preserving the desired texture of the apple snacks, regardless of the specific cultivar or drying temperature used. Through this study, with a refined understanding of the changes occurring during the drying process and the optimization of storage conditions, we can confidently offer consumers the best combination of crispy and healthy snacks that meet their expectations. © 2023 Society of Chemical Industry.

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Wine phenolic compounds, particularly proanthocyanidins (PAs), play a significant role in wine sensory characteristics, specifically bitterness and astringency. Although not consensual, flavan-3-ols and oligomeric PAs are generally considered the primary contributors to wine bitterness. Patatin, a vegetable protein fining agent, has been explored as an alternative to animal and synthetic fining agents for reducing wine bitterness. However, contradictory results exist regarding its effectiveness in removing flavan-3-ols and oligomeric PAs in red wines. In this work, a UPLC-Q-TOF MS/MS method was optimized and validated for accurately measuring flavan-3-ols, as well as dimeric and trimeric PAs, in red wines. The MS/MS analysis of flavan-3-ols, in addition to the typical fragmentation described in the literature, revealed an intense mass fragment resulting from the loss of C3O2 and C3O2 + H2O from the parent ion. It was observed that flavan-3-ols and PAs undergo oxidation during sample preparation, which was reversed by the addition of 5 g/L of ascorbic acid. The method demonstrated good linearity range (2 mg/L to 20 mg/L), detection limit (0.3 mg/L to 0.7 mg/L), quantification limit (0.8 mg/L to 2.2 mg/L), precision (repeatability 2.2% to 7.3%), and accuracy (recovery 98.5% to 100.5%). The application of patatin at different doses (5 g/L to 30 g/L) in two different red wine matrices did not reduce the levels of monomeric, dimeric, and trimeric PAs in red wines. However, similar behaviors were observed for pea protein and gelatin. Therefore, wine fining trials and efficiency measurements of the treatments in each matrix are strongly advised.

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The colour of the different Port wine styles and indication of age (IOA) categories is a distinctive quality parameter influenced by the grapes and ageing process. The impact of Port wine styles and IOA on phenolic composition is mostly unknown. This work aims to study the chromatic characteristics (CIELab) and their relation with the phenolic composition of White, Tawny, and Ruby Port wines and evaluate the feasibility of its utilisation for their discrimination. Port wine styles and IOA categories can be discriminated by their chromatic characteristics, using different data analysis models. The higher b* values, corresponding to the brownish/yellowish colour of Tawny and White Ports belonging to higher IOA categories, seem more related to the sugar browning than the oxidative change in phenolic compounds. However, this last process is essential for the red colour (a*) decrease of Tawny Port wines with higher IOA.

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An accurate and precise Multiple Headspace Solid-Phase Microextraction (MHS-SPME) method was developed and validated for quantifying the volatile composition of White and Tawny Port wines. SPME extraction conditions were optimised using a four-factor three-level Box-Behnken design with three blocks and two replications. Optimal extraction conditions were similar for both Port wines. The method showed good linearity (0.001-50 mg/L), precision (<5%), and detection limits (<1µg/L), well below the olfactory detection threshold. Recoveries higher than 95 % were obtained. Twenty-three aroma compounds were quantified in Tawny and, for the first time, in White Port wines, including five acids, fourteen esters, the most abundant class, and four norisoprenoids, whose levels apparently increased with age. White Port wines had a lower abundance of aroma compounds. Results show that this MHS-SPME method is suitable for analysing volatile composition of White and Tawny Port wines, with reduced costs, manipulation time and eliminating matrix effects.

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Under climate change threats, there is a growing need to adapt the conventional agronomic practices used in rainfed olive orchards by sustainable practices, in order to ensure adequate crop yield and olive oil quality and to preserve soil health. Therefore, for two years, the effects of conventional tillage practice (T) and two sustainable soil management strategies, a leguminous cover crop (LC) and its combination with natural zeolites (ZL), on the yield, fatty acid composition, polyphenolic profile and quality indices of olive fruits and oil were evaluated. Crop yield was significantly increased by LC and ZL in the first year. Although in the second year no significant differences were verified, the cumulative yield increased significantly by 31.6% and 35.5% in LC and ZL trees, respectively. LC enhanced the moisture and size of olives, while ZL increased, in general, the concentrations of oleuropein, verbascoside, caffeic acid and epicatechin, as well the oleic/linoleic ratio in fruits and the levels of 3,4-dihydroxyphenylglycol, tyrosol, verbascoside and caffeic acid in olive oil. Despite the higher concentration of total phenols in the fruits and oil from T trees in the warmer and dryer year, the quality of the oil decreased, mainly when compared with ZL, as evidenced by the peroxide value and K232 and K270 coefficients. In short, both sustainable soil management strategies appear to be promising practices to implement in olive orchards under rainfed conditions, but the innovative strategy of combining zeolites with legume cover crops, first reported in the present study, confers advantages from a nutritional and technological point of view. Nevertheless, studies subjected to the long-term use of these practices should be conducted to ensure the sustainability of the crop yield and olive oil quality.

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Thymus carnosus Boiss. is a near-threatened species, and, as for many species, its potential for medicinal purposes may be lost if measures towards plant protection are not taken. A way of preserving these species is to increase knowledge about their medicinal properties and economic potential. Thus, with the objective of studying the potentiality of introducing T. carnosus as a crop, the stability of the phytochemical profile of T. carnosus was studied during a period of three years by comparing the phytochemical profile of extracts obtained from plants harvested in two different edaphoclimatic locations, as well as by comparing the respective bioactivities, namely, antioxidant, antidiabetic, antiaging, and neuroprotective activities. It was reported, for the first time, the effect of annual variation and geographic location in the phytochemical composition of aqueous decoction and hydroethanolic extracts of T. carnosus. In addition, the presence of two salvianolic acid B/E isomers in T. carnosus extracts is here described for the first time. Despite the variations in phytochemical composition, according to harvesting location or year, T. carnosus extracts maintain high antioxidant activity, assessed by their capacity to scavenge ABTS•+, •OH , NO•, O2•- radicals, as well as to prevent ß-carotene bleaching. All extracts presented significant potential to inhibit acetylcholinesterase (AChE), tyrosinase, and α-glucosidase, denoting neuroprotective, anti-aging, and anti-diabetic potential. In conclusion, the vegetative stage and location of harvest are key factors to obtain the maximum potential of this species, namely, a phytochemical profile with health benefit bioactivities.

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The potato chip industry generates brownish frying residues, which are usually landfilled. While spent frying oil has value as biodiesel, the defatted brownish water-soluble extract (BrE) does not yet have an application. In this work, it was hypothesized that BrE can be a source of compounds for active packaging. BrE is composed of carbohydrates (66.9%), protein (5.7%), and a small amount of phenolics and esterified fatty acids. When incorporated into starch-based formulations and casted, BrE at 5%, 10%, and 15% w/w (dry starch weight) conferred a yellowish coloration while maintaining the transparency of neat films. The BrE increased the films' traction resistance, elasticity, and antioxidant activity while decreasing their hydrophilicity. Furthermore, starch/15% BrE-based films showed diminished water vapor and good UV-light barrier properties. Their contact with sliced cheese did not change the products' hardness during storage (14 days). Weight loss of the cheese was observed after 7 days of storage, stabilizing at 6.52%, contrary to the cheese packed in polyamide (PA)/polyethylene (PE), already used in food packaging. The cheese packed in the starch/15% BrE-based films showed a significant yellowish darkening and lower content of volatile oxidation products compared to the PA/PE. Therefore, BrE revealed to have compounds with the potential to tune the performance of starch-based films for food packaging.

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Natural products used for their health-promoting properties have accompanied the evolution of humanity. Nowadays, as an effort to scientifically validate the health-promoting effects described by traditional medicine, an ever-growing number of bioactivities are being described for natural products and the phytochemicals that constitute them. Among them, medicinal plants and more specifically the Thymus genus spp., arise as products already present in the diet and with high acceptance, that are a source of phytochemicals with high pharmacological value. Phenolic acids, flavonoid glycoside derivatives, and terpenoids from Thymus spp. have been described for their ability to modulate cell death and survival pathways, much-valued bioactivities in the pharmaceutical industry, that continually sought-after new formulations to prevent undesired cell death or to control cell proliferation. Among these, wound treatment, protection from endogenous/exogenous toxic molecules, or the induction of selective cell death, such as the search for new anti-tumoral agents, arise as main objectives. This review summarizes and discusses studies on Thymus spp., as well as on compounds present in their extracts, with regard to their health-promoting effects involving the modulation of cell death or survival signaling pathways. In addition, studies regarding the main bioactive molecules and their cellular molecular targets were also reviewed. Concerning cell survival and proliferation, Thymus spp. present themselves as an option for new formulations designed for wound healing and protection against chemicals-induced toxicity. However, Thymus spp. extracts and some of their compounds regulate cell death, presenting anti-tumoral activity. Therefore Thymus spp. is a rich source of compounds with nutraceutical and pharmaceutical value.

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