Search Results (90)

Clay minerals are promising candidates for caffeine removal due to their environmental friendliness and natural abundance. In this study, a commercially available bentonite was modified by Na⁺ exchange and characterized using Fourier transform infrared spectroscopy, X-ray diffractometry, scanning electron microscopy, zeta potential measurements, and specific surface area analysis. Caffeine adsorption was rapid, reaching equilibrium within 15 min. Adsorption isotherms for caffeine and its metabolites (theobromine, paraxanthine, and theophylline) in pure water were analyzed at 25.0 ± 0.5 °C using Langmuir and Freundlich models, both individually and in mixtures. Only caffeine exhibited favorable adsorption behavior, fitting the Langmuir equation, which allowed for the determination of a maximum adsorption capacity of 20 ± 3 mg/g, regardless of metabolite presence. The removal exceeded 85% of the caffeine from a 5.0 mg/L solution. The adsorption affinity of the studied compounds toward Na⁺-exchanged bentonite followed the order: caffeine >>> theobromine > paraxanthine ~ theophylline. The modified bentonite was then tested for caffeine removal from beverages and synthetic urine, achieving removal efficiencies exceeding 87%. To our knowledge, this is the first study investigating the effect of major caffeine metabolites on adsorption rates across different sample matrices, such as artificial urine, cola soda, soluble coffee, energy drinks, green tea, and yerba mate. Full article

Lipid vesicles, liposomes and phytosomes have been gaining significant attention in various applications for phytochemical preservation. Furthermore, yerba mate (Ilex paraguariensis) contains a high content of bioactive compounds with functional properties; however, its liquid extract exhibits limited stability. For the first time, lipid vesicles containing yerba mate extract were produced and characterized. They were prepared using pure or purified phosphatidylcholine (PC) and n-hexane as a solvent via the reverse phase evaporation method. Their characterization was conducted using Fourier transform infrared spectroscopy (FTIR), UV–vis spectroscopy, Zeta potential (PZ), and dynamic light scattering (DLS). The decrease or absence of FTIR bands and UV–vis absorbance (325 nm) from the yerba mate extract suggests the successful dispersion of yerba mate extract in the liposome membrane, ensuring its encapsulation or complexation. Additionally, the size of lipid vesicles decreased from 625.1 nm to 440.5 nm (pure PC) and from 690.0 nm to 518.6 nm (purified PC) after the addition of yerba mate extract PZ values showed a slight change in all vesicles enhancing colloidal stability. This, combined with the reduction observed in DLS, suggests membrane reorganization, leading to the formation of unilamellar liposomes. Our observations indicate the possible formation of phytosomes, although additional studies are necessary to confirm this mechanism. Full article

This study investigated the levels of four polycyclic aromatic hydrocarbons (BaA, CHR, BbF, and BaP) in 11 types of 100 commercially available tea products using gas chromatography–mass spectrometry (GC-MS), and also evaluated potential dietary risks, toxic equivalency (TEQ), and margin of exposure (MOE). Method validation demonstrated strong linearity of the calibration curves for all four PAHs (R² > 0.99) over a concentration range of 1–20 μg/kg. The LOD for the four PAHs ranged from 0.0610 to 0.1534 μg/kg in the solid matrix and from 0.0035 to 0.0064 μg/kg in the liquid matrix, with corresponding LOQ ranging from 0.1849 to 0.4648 μg/kg in the solid matrix and from 0.0107 to 0.0194 μg/kg in the liquid matrix. All recovery rates were within the acceptable range, demonstrating satisfactory performance, and both intraday and interday accuracy and precision were within acceptable limits, meeting international validation criteria. Among the samples, yerba mate tea (33.58 μg/kg), herbal tea (24.05 μg/kg), and oolong tea (23.21 μg/kg) showed the highest Σ4PAH concentrations. Based on these results, TEQ_BaP and MOE values were calculated for the positive samples. All three teas with detectable PAHs exhibited MOE values above 10,000, indicating a low level of potential carcinogenic risk. However, the presence of PAHs in certain tea types highlights the importance of ongoing monitoring, regulatory oversight, and risk communication to ensure consumer safety. Full article

A unique isotonic sports drink (ISD) was created in this study using a pilot-scale short-wave ultraviolet light (UV-C, 892 mJ/cm², 20 °C) assisted by mild heat (UV-C/H, 534 mJ/cm², 50 °C), which was followed by the addition of yerba mate (Ilex paraguariensis) extract (YME). Consumer perception and microbiological and physicochemical stability during refrigerated storage (4 °C/23 d) were assessed for the ISD. Alicyclobacillus acidoterrestris (AA) spores and cocktails of yeasts and Escherichia coli were considerably inactivated by UV-C/H. The TEM and SEM micrographs showed that AA evidenced sustained severe structural damage. Furthermore, UV-C/H completely inactivated the native microbiota, while YME incorporation increased the initial aerobic mesophilic and mold-and-yeast populations by 0.48 and 0.70 log cycles, remaining stable during storage. YME addition enhanced total polyphenols, flavonoids and antioxidant activity by 2.7–3.7, 16.5–16.7 and 6.6–24.0 times compared to the untreated ISD and ISD-UVC/H samples. Except for sedimentation and turbidity, the other physical characteristics mostly did not change (going from 1494 ± 382 to 2151 ± 106 NTU). The initial 5-HMF value in the ISD was raised by UV-C/H treatment and YME addition. Notwithstanding, it stayed below the allowed threshold throughout storage. ISD-UVC/H+YME had a high overall acceptability score; 60% of panelists gave the drink a score of seven or higher. Additionally, the herbal taste of YME was well liked, and its bitterness was perceived as mild. These findings suggest that including YME and the UV-C/H treatment can produce an ISD of superior quality with distinct sensory attributes. Full article

Background/Objectives: In Latin America, yerba mate (YM) is a popular infusion processed from the leaves and stems of Ilex paraguariensis. YM has been shown to have anti-inflammatory properties in several studies, although the effect of YM on multiple sclerosis (MS) remains elusive. The purpose of this study was to examine the effect of YM on the development of MS, by using the experimental autoimmune encephalomyelitis (EAE) mouse model while also evaluating its effect over infiltration of immune cells into the central nervous system (CNS) and regulatory T cell (Treg) function. Methods: YM or vehicle were administrated to mice daily by oral gavage for seven days prior to EAE induction and during the entire course of the disease. EAE score was recorded daily, and immune cell infiltration into the CNS was measured by flow cytometry and immunofluorescence. Results: Our results showed that YM administration decreases EAE symptoms and immune cell infiltration into the CNS, along with reducing demyelination, compared to the vehicle treatment. Moreover, an increase in the Treg population, immune cells capable of generating tolerance and decreased inflammation, was observed in mice receiving YM, together with improved Treg suppressive capabilities after YM treatment in vitro. Conclusions: In summary, we showed that YM promotes an immunosuppressive environment by modulating Treg function, reducing EAE symptoms and immune cell infiltration into the brain, and suggesting that YM consumption could be a good cost-effective treatment for MS. Full article

Background/Objectives: Yerba maté (YM), a traditional herbal beverage made from Ilex paraguariensis, contains bioactive compounds like polyphenols and alkaloids known for their metabolic benefits. This study investigates YM’s incretin effects, focusing on glucagon-like peptide-1 (GLP-1) and gastric inhibitory polypeptide (GIP). Methods: Male and female C57BL/6 mice were supplemented with YM for four weeks. Post-supplementation, GLP-1 and GIP gene expression levels were analyzed in jejunal mucosa, and plasma hormone concentrations were measured. Additionally, in vitro experiments were conducted using GLUTag L-cells to evaluate the direct effects of YM and its metabolites, including ferulic acid and dihydroferulic acid, on GLP-1 secretion. Gene expression analysis involved quantitative real-time PCR, while hormone levels were assessed via ELISA. Results: YM supplementation significantly increased GLP-1 gene expression and plasma GLP-1 levels compared to controls, with no changes observed in GIP expression or plasma levels. Direct treatment of GLUTag L-cells with YM did not enhance GLP-1 secretion. However, dihydroferulic acid, a microbial metabolite of ferulic acid, markedly stimulated GLP-1 production in L-cells, highlighting a role of gut-mediated metabolism in YM’s incretin effects. Conclusions: YM selectively upregulates GLP-1 pathways without affecting GIP, likely through gut-mediated mechanisms. These findings suggest YM as a promising nutraceutical for incretin modulation and metabolic disorder management. Further studies should explore the interplay between YM, the gut microbiota, and incretin pathways to fully realize its therapeutic potential. Full article

Dioecious species show a division of labor expressed through the differentiated manifestation of resource acquisition. We hypothesized that the expression of secondary sexual dimorphism (SSD) in the leaf gas exchange of yerba mate would be more intensive in females than in males to permit females the carbon investments necessary to finish the reproductive cycle. This species can present two growth units annually (GU1-fall and GU2-spring) intercalated with two rest periods (R1-summer and R2-winter). The leaf area index (LAI) and the diurnal courses of leaf photosynthesis (A_net), stomatal conductance (g_s), leaf transpiration (E), intercellular CO₂ concentration (C_i), water use efficiency (WUE), and instantaneous carboxylation efficiency (A_net/C_i) were estimated in female and male plants of yerba mate during four periods of annual rhythmic growth in monoculture (MO) and agroforestry (AFS). Leaf gas exchanges varied over the annual rhythmic growth and were more intensive under MO than under AFS. A_net, A_net/C_i ratios, and WUE were higher in females than in males during the summer (R1) and spring (GU2). Also, g_s and E were more intensive in females than males during the summer. Oppositely, higher WUE in males than in females was observed during the fall (GU1) and winter (R2), with males also showing a higher A_net/C_i ratio during the winter and higher E during the spring (GU2). Despite the strong effect of the cultivation system on LAI and leaf gas exchange traits over the diurnal course, SSD expression was rarely modified by the cultivation system, being expressed only in MO for E during the spring (GU2) and WUE during the winter (R2). High WUE in males during the winter would benefit plants during cold and dry periods, improving the balance between carbon acquisition and water loss through transpiration. On the other hand, high A_net during the summer and spring could be considered as a general fitness strategy of female plants to improve photoassimilate supply and support their additional reproduction costs. Full article

The properties of two hybrid nanoarchaeosomes (hybrid nanoARCs) made of archaeolipids extracted from the halophilic archaea Halorubrum tebenquichense and combining the properties of archaeolipid bilayers with metallic nanoparticles are explored here. BS-nanoARC, consisting of a nanoARC loaded with yerba mate (Ilex paraguariensis) extract (YME)-biogenic silver nanoparticles (BSs), and [BS + BS-nanoARC], consistent of a BS-nanoARC core covered by an outer shell of BSs, were structurally characterized and their therapeutic activities screened. By employing 109 ± 5 µg gallic acid equivalents (GAEs) and 73.4 µg chlorogenic acid/ YME mg as a silver reductive agent, spherical, heterogeneously sized (~80 nm diameter), −27 mV ζ potential, 90% Ag⁰ and λ_max 420 nm BSs were obtained. We further prepared ~100–200 nm diameter, −57 mV ζ potential BS-nanoARC and ~300 nm diameter, −37 mV ζ potential [BS + BS-nanoARCs]. Freshly prepared and nebulized BS-nanoARCs reduced the release of TNF-α, IL-6 and IL-8 by LPS-irritated THP-1-macrophages and were highly anti-planktonic against S. aureus (MIC₉₀: 13 ± 0.8 µg Ag/mL). While the nanoARCs and BS-nanoARCs were innocuous, freshly prepared [BS + BS-nanoARCs] magnified the cytotoxicity of BSs (IC₅₀ 12 µg Ag/mL vs. IC₅₀ ~36 µg Ag/mL) on A549 cells. Such cytotoxicity remained after 30 days in the dark at 4 °C, while that of BSs was lost. Freshly prepared BSs also lost activity upon nebulization, whereas freshly prepared [BS + BS-nanoARCs] did not. However, the cytotoxicity of the [BS + BS-nanoARCs] was also lost when nebulized after 30 days of storage. Despite the harmful effects of storage and mechanical stress on the structure of the more active [BS + BS-nanoARCs], hybrid nanoARCs are promising examples of nanomedicines combining the properties of archaeolipids with antimicrobial silver nanoparticles and anti-inflammatory polyphenols that could complement oncologic therapies, reducing the usage of classical antitumoral agents, corticosteroids, and, importantly, of antibiotics, as well as their waste. Full article

Yerba mate beverage is prepared from Ilex paraguariensis grown in South America, and its popularity still is increasing. The aim of this study was to show the differences in the content of antioxidant compounds between hot- and cold-prepared mate beverages. The antioxidant capacity of the infusions was tested using the Folin–Ciocalteu, ABTS, and DPPH assays. A comprehensive analysis of different phenolic and other constituents was performed with the use of high-performance liquid chromatography–tandem mass spectrometry (LC-MS/MS). The hot-prepared infusions on average contain considerably more active compounds than the cold-prepared infusions, which resulted in greater antioxidant activity of hot-prepared beverages. While the hot-prepared infusions of pure yerba mate contained a similar amount of bioactive compounds as those with different additives, for cold-prepared beverages, greater antioxidant activity was found for samples containing additives. In both conditions, the lowest antioxidant activity was noted for Ilex guayusa, which contained less rutin, caffeoylquinic acids, dicaffeoylquinic acids, and theobromine, but more caffeine. Full article

Enzyme immobilization is a crucial method in biotechnology and organic chemistry that significantly improves the stability, reusability, and overall effectiveness of enzymes across various applications. Lipases are one of the most frequently applied enzymes in food. The current study investigated the potential of utilizing selected agri-food and waste materials—buckwheat husks, pea hulls, loofah sponges, and yerba mate waste—as carriers for the immobilization of Sustine^® 121 lipase and Yarrowia lipolytica yeast biomass as whole-cell biocatalyst and lipase sources. Various lignocellulosic materials were pretreated through extraction processes, including Soxhlet extraction with hexane and ethanol, as well as alkaline and acid treatments for loofah sponges. The immobilization process involved adsorbing lipases or yeast cells onto the carriers and then evaluating their hydrolytic and synthetic activities. Preparations’ activities evaluation revealed that alkaline-pretreated loofah sponge yielded the highest hydrolytic activity (0.022 U/mg), while yerba mate leaves under brewing conditions demonstrated superior synthetic activity (0.51 U/mg). The findings underscore the potential of lignocellulosic materials from the agri-food industry as effective supports for enzyme immobilization, emphasizing the importance of material selection and pretreatment methods in optimizing enzymatic performance through giving an example of circular economy application in food processing and waste management. Full article

Yerba mate (YM) is an important crop derived from the cultivation of the native tree Ilex paraguariensis in northeastern Argentina, used for the preparation of mate infusion, which is widely consumed in South America. This study aimed at assessing the environmental impact, namely of CO₂ equivalent (CO₂eq.) emissions, of the YM value chain while identifying environmental hotspots along the production chain, from nursery up to transport. A cradle-to-wholesale approach was carried out, considering as the main functional unit 1 kg of commercial YM produced in Misiones Province and transported to Buenos Aires, the largest YM market in the world. Primary data were gathered from representative nurseries and plantations of the region; processing and packaging data were collected from a local cooperative, while the assessment of the impact due to truck transport was performed considering a distance of 1200 km from Buenos Aires. All the processes were analyzed using LCA methodology following the guidelines outlined in the ISO 14044 regulation (EN ISO 14044); the GaBi software (Sphera Solution, Inc., Chicago, IL, USA), updated to version 10.7.21.8, was used for process modeling, while the CML 2001 calculation method, updated as of the latest release in August 2016, was used to calculate the impacts. The results (1.24 kg CO₂eq./kg. YM produced in Misiones and transported to Buenos Aires) show that the cultivation phase of YM has very little impact, while most of the emissions are related to the drying phase and the subsequent transportation from the production area to Buenos Aires. Full article

Ilex paraguariensis (IP) extract was added to prepare edible films using a central rotational composite design (CCRD) 2² with IP extract and sorbitol concentrations as variables. The IP extract was characterized by color parameters, total phenolic content, caffeine, flavonoids, and chlorophyll content, and antioxidant activity and the edible films were assessed for the same analysis and thickness, water vapor permeability (WVP), solubility in water, fluorescence, photodegradation and UV/Vis light barrier, FT-IR, thermogravimetry, and differential exploratory colorimetry. Sorbitol increased thickness and WVP, while the extract influenced the concentration of phenolic compounds in the films. The optimum concentrations of extract and sorbitol were 10% and 15%, respectively. Films presented thermal resistance (until 230 °C) and an excellent barrier to UV light. Furthermore, these films could carry compounds originally in IP, showing good functional properties concerning the water vapor barrier (showing a great variation scale due to the possibility to increase sorbitol or not, between 3.33 and 5.27 g mm/m² day KPa). The films showed great potential to replace conventional primary packaging, and if consumed with food, as a bullet paper, they can add nutritional value to the packaged product. Full article

We describe the antioxidant capability of scavenging the superoxide radical of several tea and yerba mate samples using rotating ring–disk electrochemistry (RRDE). We directly measured superoxide concentrations and detected their decrease upon the addition of an antioxidant to the electrochemical cell. We studied two varieties of yerba mate, two varieties of black tea from Bangladesh, a sample of Pu-erh tea from China, and two components, caffeic acid and chlorogenic acid. All of these plant infusions and components showed strong antioxidant activities, virtually annihilating the available superoxide concentration. Using density functional theory (DFT) calculations, we describe a mechanism of superoxide scavenging via caffeic and chlorogenic acids. Superoxide can initially interact at two sites in these acids: the H4 catechol hydrogen (a) or the acidic proton of the acid (b). For (a), caffeic acid needs an additional π–π superoxide radical, which transfers electron density to the ring and forms a HO₂⁻ anion. A second caffeic acid proton and HO₂⁻ anion forms H₂O₂. Chlorogenic acid acts differently, as the initial approach of superoxide to the catechol moiety (a) is enough to form the HO₂⁻ anion. After an additional acidic proton of chlorogenic acid is given to HO₂⁻, three well-separated compounds arise: (1) a carboxylate moiety, (2) H₂O₂, and a (3) chlorogenic acid semiquinone. The latter can capture a second superoxide in a π–π manner, which remains trapped due to the aromatic ring, as for caffeic acid. With enough of both acids and superoxide radicals, the final products are equivalent: H₂O₂ plus a complex of the type [X-acid–η–O₂], X = caffeic, chlorogenic. Chlorogenic acid (b) is described by the following reaction: 2 O₂^•− + 2 chlorogenic acid → 2 chlorogenic carboxylate + O₂ + H₂O₂, and so, it acts as a non-enzymatic superoxide dismutase (SOD) mimic, as shown via the product formation of O₂ plus H₂O₂, which is limited due to chlorogenic acid consumption. Caffeic acid (b) differs from chlorogenic acid, as there is no acidic proton capture via superoxide. In this case, approaching a second superoxide to the H4 polyphenol moiety forms a HO₂⁻ anion and, later, an H₂O₂ molecule upon the transfer of a second caffeic acid proton. Full article

Ilex paraguariensis, commonly known as yerba mate, is a plant belonging to the holly genus Ilex and the Aquifoliaceae family, indigenous to South America, and is used for the production of yerba mate. Yerba mate is renowned for its abundance of essential nutrients and bioactive compounds. Based on test results, it can be assumed that the selection of raw material for the preparation of extracts as well as the extraction method significantly influence the final content of biologically active compounds in the extracts. Consequently, this variability impacts the ultimate concentration of biologically active substances within the end product, potentially influencing human consumption. The present study aimed to quantify and compare the content of selected biological active compounds in supplements and products containing I. paraguariensis extracts, along with organic yerba mate dried through a smoke-free process, available in the European market (P-1–P-10). The evaluation focused on antioxidant substances such as neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, 4-feruloylquinic acid, isochlorogenic acid, rutoside astragalin, and caffeine. Additionally, the concentration of specific macro and trace elements was ascertained. The antioxidant compound makeup differs between methanol-extracted samples and aqueous extracts. In both cases, methanol extracts, particularly those in instant and traditional herb forms, showed the highest content of organic compounds with antioxidant properties (such as phenolic compounds and caffeine). The highest content of chlorogenic acid was detected in both methanol (14.7412 mg/g d.w.) and water (8.3120 mg/g d.w.) extracts in product P-4. The caffeic acid content ranged from 0.1491 mg/g d.w. to 1.7938 mg/g d.w. in methanol extracts and from 0.0760 mg/g d.w. to 0.4892 mg/g d.w. in water extracts. The neochlorogenic acid content ranged from 2.6869 to 23.9750 mg/g d.w. in ethanol extracts and from 0.4529 to 10.2299 mg/g d.w. in water extracts. Therefore, the traditional preparation of yerba mate as a water infusion does not fully exploit the raw material’s potential. Among the tested products, only the dietary supplement in capsule form contained protocatechuic acid, which was not present in any other tested products. Conversely, compounds characteristic of yerba mate found in other preparations were absent in this supplement. The caffeine content was also the lowest in this product. The determined content of active substances did not consistently match the declarations made by producers if stated on the packaging. Full article

A series of activated carbons (YMBC) obtained from yerba mate twig residue (YMT) were prepared by chemical (H₃PO₄) and thermal activation. Five materials were synthesized, varying the carbonization temperature (400–600 °C under N₂ atmosphere) and H₃PO₄:YMT ratio (60–80 wt%). They were physicochemically and texturally characterized by SEM-EDX, BET, FT-IR, and ³¹P MAS-NMR. Potentiometric titration with the n-butylamine technique was used to evaluate their acidic properties. The materials exhibited a high specific surface area (572 m² g⁻¹ < S_BET < 1031 m² g⁻¹) and mesoporosity (67% < S_meso/S_BET < 93%). The results showed that the acid strength and the number of acid sites increased with the H₃PO₄:YMT ratio and decreased with the calcination temperature increment. The FT-IR and ³¹P characterization revealed the presence of H_n+2P_nO_3n+1 species firmly (via P-O-C linkages) and loosely attached (by electrostatic interaction). The latter were successfully removed by refluxing the material in water or n-propanol. The optimal reaction conditions were applied to the synthesis of other levulinic acid esters using YMBC-500-70_NP as a catalyst. Furthermore, the effective separation of the product combined with the use of a recyclable catalyst resulted in a clean and environmentally friendly strategy for the synthesis of alkyl levulinates, bioproducts of relevance to the biorefinery industry, which can be applied as fragrances, flavoring agents, as well as fuel additives. Full article