The bitter side of teas: Pesticide residues and their impact on human health.

Tea (Camellia sinensis) is one of the most widely consumed non-alcoholic beverages globally, known for its rich composition of bioactive compounds that offer various health benefits to humans. However, the cultivation of tea plants often faces challenges due to their high vulnerability to pests and diseases, resulting in the heavy use of pesticides. Consequently, pesticide residues can be transferred to tea leaves, compromising their quality and safety and potentially posing risks to human health, including hormonal and reproductive disorders and cancer development. In light of these concerns, this review aims to: (I) present the maximum limits of pesticide residues established by different international regulatory agencies; (II) explore the characteristics of pesticides commonly employed in tea cultivation, encompassing aspects such as digestion, bioaccessibility, and the behavior of pesticide transfer; and (III) discuss the effectiveness of detection and removal methods for pesticides, the impacts of pesticides on both tea plants and human health and investigate emerging alternatives to replace these substances. By addressing these critical aspects, this review provides valuable insights into the management of pesticide residues in tea production, with the goal of ensuring the production of safe, high-quality tea while minimizing adverse effects on human health.

Functional properties of bioactive compounds from Spirulina spp.: Current status and future trends.

Functional foods show non-toxic bioactive compounds that offer health benefits beyond their nutritional value and beneficially modulate one or more target functions in the body. In recent decades, there has been an increase in the trend toward consuming foods rich in bioactive compounds, less industrialized, and with functional properties. Spirulina, a cyanobacterium considered blue microalgae, widely found in South America, stands out for its rich composition of bioactive compounds, as well as unsaturated fatty acids and essential amino acids, which contribute to basic human nutrition and can be used as a protein source for diets free from animal products. In addition, they have colored compounds, such as chlorophylls, carotenoids, phycocyanins, and phenolic compounds which can be used as corants and natural antioxidants. In this context, this review article presents the main biological activities of spirulina as an anticancer, neuroprotective, probiotic, anti-inflammatory, and immune system stimulating effect. Furthermore, an overview of the composition of spirulina, its potential for different applications in functional foods, and its emerging technologies are covered in this review.

Investigation on brewer's spent yeast as a bio-vehicle for encapsulation of natural colorants from pumpkin (Cucurbita moschata) peels.

Brewer's spent yeast (BSY) Saccharomyces cerevisiae has been explored as a bio-vehicle for the encapsulation of bioactive compounds and as a delivery system. The main objectives of this work were to encapsulate carotenoids from pumpkin peel extract using BSY as an encapsulating agent and to evaluate the influence of ultrasound treatment on the carotenoid incorporation, stability and release. The powders produced by atomization of the suspension of BSY in the extract from pumpkin peels showed physical and microbiological stability during storage, presenting low values of water activity (<0.406), moisture content (<7.0%) and hygroscopicity (<6.8 g per 100 g), characteristics of greatest importance for powder formulations. Regarding the chemical stability of the incorporated carotenoids, there was a decline in carotenoid content in the first 30 days (p ≤ 0.01), although stabilization was achieved up to the 75th day. The best retention of carotenoids (273.3 µg g-1 of particles) was obtained by applying ultrasound treatment before atomization, which probably led to the adsorption of carotenoids onto yeasts. Ultrasound also showed a positive effect on the color protection of powders during storage and on the protection of compounds under simulated gastrointestinal digestion. BSY released the carotenoids gradually during the digestion and higher carotenoid release occurred in the intestinal phase with bioaccessibility values of 26.9 and 30.3%. Yeasts are a suitable carrier material and show promising characteristics for technological application.

The Importance of Antioxidant Biomaterials in Human Health and Technological Innovation: A Review.

Biomaterials come from natural sources such as animals, plants, fungi, algae, and bacteria, composed mainly of protein, lipid, and carbohydrate molecules. The great diversity of biomaterials makes these compounds promising for developing new products for technological applications. In this sense, antioxidant biomaterials have been developed to exert biological and active functions in the human body and industrial formulations. Furthermore, antioxidant biomaterials come from natural sources, whose components can inhibit reactive oxygen species (ROS). Thus, these materials incorporated with antioxidants, mainly from plant sources, have important effects, such as anti-inflammatory, wound healing, antitumor, and anti-aging, in addition to increasing the shelf-life of products. Aiming at the importance of antioxidant biomaterials in different technological segments as biodegradable, economic, and promising sources, this review presents the main available biomaterials, antioxidant sources, and assigned biological activities. In addition, potential applications in the biomedical and industrial fields are described with a focus on innovative publications found in the literature in the last five years.

Development of natural pigments microencapsulated in waste yeast Saccharomyces cerevisiae using spray drying technology and their application in yogurt.

Although Saccharomyces cerevisiae has shown potential utilization as a bio-vehicle for encapsulation, there are no reports about the functionality of natural colorants encapsulated using yeast cells. The main objectives of this study were to produce natural food coloring by encapsulating extracts from grape pomace (GP) and jabuticaba byproducts (JB) in brewery waste yeast and evaluate the functionality of the pigments by their incorporation into yogurts. Particles produced by the encapsulation of extracts from GP and JB in S. cerevisiae using 5% of yeast had the highest encapsulation efficiencies for both anthocyanins (11.1 and 47.3%) and phenolic compounds (67.5 and 63.6%), the highest concentration of both bioactives during storage and stable luminosity. Yogurts showed a pseudoplastic behavior and were considered weak gels. Colored yogurts had acceptance indexes between 73.9 and 81.4%. This work evidenced the utilization of enriched yeasts as coloring agents and interesting additives for the production of functional foods.

Microencapsulation of carotenoid-rich materials: A review.

Carotenoids are natural pigments that present several bioactive properties, including antioxidant, anticarcinogenic and provitamin A activities. However, these compounds are susceptible to degradation when exposed to a number of conditions (e.g. light, heat, oxygen), leading to loss of benefits and hampering their application in food products. Their hydrophobicity also makes incorporation into water-based foods more difficult. Microencapsulation techniques have been applied for decades to provide stability to carotenoid-rich extracts under typical conditions of processing and storage of foods, besides offering several other advantages to the use and application of these materials. This work reviews the recent advances in the microencapsulation of carotenoid-rich extracts, oils and oleoresins from varying sources, evidencing the technologies applied to encapsulate these materials, the effects of encapsulation on the obtained particles, and the impact of such processes on the bioaccessibility and release profile of carotenoids from microparticles. Moreover, recent applications of carotenoid-rich microparticles in food products are discussed. Most of the applied processes were effective in improving different aspects of the encapsulated materials, especially the stability of carotenoids during storage, resulting in microparticles with promising properties for future applications in food products. However, the lack of information about the effects of microencapsulation on carotenoids during processing of model foods, the sensory acceptance of enriched food products and the bioaccessibility and bioavailability of microencapsulated carotenoids reveals gaps that should be explored in the future.

Utilization of grape pomaces and brewery waste Saccharomyces cerevisiae for the production of bio-based microencapsulated pigments.

This research approaches the utilization of brewery waste yeast Saccharomyces cerevisiae as a vehicle for the encapsulation and protection of phenolic compounds from Cabernet Sauvignon and Bordeaux grape pomace extracts. The main purpose of this research was to enrich the biomass of yeast to investigate its potential as a novel vehicle for further application as pigment or functional ingredient. The obtained powders presented characteristics appropriated for storage, such as low water activity (<0.289), hygroscopicity (<13.71 g/100 g) and moisture (<7.10%) and particle sizes lower than the sensory perceptible (<11.45 µm). This work proved that yeasts were loaded after spray-drying, thus, they might be considered as biocapsules. Furthermore, the bioaccessibility of encapsulated phenolic compounds from Bordeaux and Cabernet Sauvignon extracts was 34.96% and 14.25% higher compared to their respective free extracts, proving that yeasts are not only biocapsules of easy application, but also a biological material capable of protecting and delivering the compounds during gastrointestinal digestion.

Análise da citotoxicidade de um gel clareador com 10% de peróxido de hidrogênio sobre células odontoblastóides de acordo com a espessura do substrato dental / Analysis of the cytotoxicity of a 10% hydrogen peroxide bleaching gel to odontoblast-like cells according to the thickness of dental substrate

Objetivo: Avaliar a citotoxicidade de um gel clareador contendo 10% de peróxido de hidrogênio (H2O2), aplicado sobre discos de esmalte/dentina simulando diferentes espessuras dentais. Material e método: Discos com 2,3; 3,5; e 4,0 mm de espessura foram obtidos para simular incisivos centrais inferiores, incisivos centrais superiores e segundos pré-molares superiores, respectivamente. Para cada espessura, o gel com 10% de H2O2 foi aplicado sobre o esmalte por 3x 15 min, 1x 15 min ou 1x 5 min. O protocolo 35% H2O2 3x 15 min foi empregado como controle positivo (CP), e nenhum tratamento foi realizado no controle negativo (CN). Células odontoblastóides MDPC-23 foram expostas por 1 h aos componentes da difusão trans-amelodentinária coletados imediatamente após o clareamento, sendo realizada análise da viabilidade celular, estresse oxidativo, deposição de nódulos de mineralização, bem como a quantificação da difusão de H2O2 pelos discos. Resultados: O gel com 10% de H2O2 não promoveu redução significativa da viabilidade celular em relação ao CN para todos os protocolos e espessuras testadas, resultando em valores de difusão de H2O2 significativamente inferiores ao CP. Apenas o protocolo 10% 3x 15 min aplicado sobre os discos simulando incisivos promoveu aumento no estresse oxidativo e reduziu a deposição de nódulos de mineralização em relação ao CN; porém, estes efeitos foram significativamente inferiores ao CP. Conclusão: De acordo com a metodologia usada neste estudo, foi possível concluir que, independente da espessura dental, a aplicação de um gel clareador com 10% de H2O2 por 5-45 min sobre o esmalte causa limitado efeito citotóxico sobre células pulpares.

Objective: To evaluate the cytotoxicity of a bleaching gel with 10% hydrogen peroxide (H2O2) applied onto enamel/dentin discs simulating different dental thicknesses. Material and methods: Discs with 2.3; 3.5; and 4.0 mm thickness were obtained to simulate low central incisors, upper central incisors and upper second pre-molars, respectively. For each thickness, the 10% H2O2 gel was applied for 3x 15 min, 1x 15 min or 1x 5 min. A gel with 35% H2O2 applied for 3x 15 min was used as positive control (PC) and no treatment was performed in negative control (NC). Odontoblast- like MDPC-23 cells were exposed for 1 h to the transenamel and trans-dentinal components collected immediately after bleaching. Cell viability, oxidative stress and mineralized nodule deposition were assessed as well as the quantification of H2O2 diffused through the discs. Results: The 10% H2O2 gel did not promote significant reduction on cell viability in comparison to NC for all tested protocols and thicknesses, resulting in H2O2 diffusion values significantly lower than PC. Only the protocol 10% H2O2 3x 15 min applied onto discs simulating incisors increased significantly the oxidative stress and reduced mineralized nodule deposition compared to NC; however, these effects were significantly lower than PC. Conclusion: According to the methodology employed in this laboratorial study, the application of a bleaching gel with 10% H2O2 for 5-45 min onto dental structure featured limited cytotoxicity to pulp cells, disregarding the enamel/dentin thicknesses.

Studies of Pb2+ adsorption by Moringa oleifera Lam. seeds from an aqueous medium in a batch system.

The efficiency of Moringa (Moringa oleifera Lam.) seeds for removing lead ions (Pb(2+)) from water was evaluated. Parameters such as solution pH, adsorbent mass, contact time between solution and adsorbent, isotherms, thermodynamic, kinetics, and desorption were evaluated. The maximum adsorption capacity of the biosorbent was found to be 12.24 mg g(-1). In order to verify the effectiveness of this material, comparative studies were performed with activated carbon under the same optimal conditions for the construction of isotherms and the desorption process. Average desorption rate values led to the assumption that a strong interaction took place between the adsorbents and the metal ions. Thus, it has been concluded that the biosorbent studied herein can be considered very effective and feasible for remediating Pb(2+)-contaminated solutions, since this material is itself an untreated and low-cost byproduct.

Removal of cadmium from water using by-product Crambe abyssinica Hochst seeds as biosorbent material.

The effectiveness of Crambe abyssinica Hochst seeds by-product as a biosorbent for the removal of cadmium ions from wastewater was analyzed. The biomass of crambe was characterized by scanning electron microscopy, infrared spectroscopy and determining the point of zero charge. The optimum adsorption conditions obtained were 400 mg of biomass in a solution of pH 6.0 and contact time of 60 min to remove 19.342 mg g(-1) cadmium ions. The isotherms of adsorption were constructed and, according to the mathematical linearization, the best fitting followed the Freundlich and Dubinin-Radushkevich models, describing a multilayer adsorption and chemical interaction, also confirmed by the pseudo-second order model and enthalpy value. In the desorption process, about 79% of cadmium ions that had been adsorbed were recovered. The same conditions applied for studying the isotherms of adsorption and desorption were used for comparative study with activated carbon. It was concluded that the use of crambe by-product as biosorbent for cadmium removal in wastewaters was not only a viable alternative to activated carbon, but also required no previous treatment, so it represents a sustainable material with high applicability and low environmental impact.

Desenvolvimento da cultura do milho submetida a fertilizantes orgânicos e minerais / Corn development due organic and mineral fertilizers

O trabalho teve como objetivo verificar o efeito do húmus de minhoca peletizado na cultura do milho, comparando com o uso de fertilizante mineral. O experimento foi conduzido no município de Cascavel, Estado do Paraná. Os tratamentos usados foram: 450 kg ha-1 do fertilizante mineral 8-20-20, 450 kg ha-1 de húmus de minhoca peletizado, 900 kg ha-1 de húmus de minhoca peletizado, 225 kg ha-1 de fertilizante mineral 8-20-20 mais 225 kg ha-1 de húmus de minhoca peletizado e a Testemunha constituindo o quinto tratamento. O Húmus Peletizado com 900 kg ha-1 apresentou maior produtividade e melhor viabilidade econômica, sendo mais indicado que o fertilizante mineral e a interação entre os mesmos. p

The study aimed to verify the effect of earthworm castings in corn pellets, compared with the use of mineral fertilizer. The experiment was conducted in the city of Cascavel, Parana State. The treatments were 450 kg ha1 mineral fertilizer 8-20-20, 450 kg ha-1 of earthworm castings pellets, 900 kg ha-1 of earthworm castings pellets, 225kg ha-1mineral fertilizer 8 -20-20 plus 225 kg ha-1 of earthworm castings and pelletized and the witness is the fifth treatment. Humus Pellets with 900 kg ha-1 showed higher productivity and better economic viability, being more appropriate for the mineral fertilizer and the interaction between them.

Imatinib resistance in multidrug-resistant K562 human leukemic cells.

The multidrug resistance phenotype (MDR) is one of the major causes of failure in cancer chemotherapy and it is associated with the over-expression of P-glycoprotein (P-gp or MDR1) in tumor cell membranes. A constitutive NF-kappaB activity has been observed in several haematological malignancies and this is associated with its anti-apoptotic role. In the present work, the relationship between NF-kappaB and MDR phenotype was evaluated in wild type K562 human leukemic cells (K562-WT) and in its vincristine-resistant counterpart, K562-Vinc cells. These data showed that K562-Vinc cells, which express an active P-gp, exhibited MDR phenotype. The resistant indexes (IC(50)(K562-Vinc)/IC(50)(K562-WT)) for structurally unrelated drugs like imatinib, doxorubicin and colchicine were 8.0+/-0.3, 2.8+/-0.4 and 44.8+/-8.8, respectively. The imatinib resistance was reversed by P-gp blockade suggesting the involvement of P-gp in imatinib transport. We observed that NF-kappaB was constitutively activated in both cell lines but in a lesser extent in K562-Vinc. The inhibition of NF-kappaB with BAY 11-7082 increased the cytotoxicity of imatinib in K562-Vinc cells but not in K562-WT. Further, the co-administration of imatinib and BAY 11-7082 sensitized multidrug-resistant K562 cells to cell death as detected by increased percentage of annexin V positive cells. The induced cell death in K562-Vinc cells was associated with activation of caspases 9 and 3. Finally, we provide data showing that BAY 11-7082 down-regulates the expression of P-gp suggesting that the activity of NF-kappaB could be functionally associated to this protein in K562 cells. Our results indicate that the vincristine-resistant K562 cells which developed MDR phenotype, exhibited resistance to imatinib associated with a functional P-gp over-expression. This resistance could be partially overcome by the inhibition of NF-kappaB pathway.

[Different enzymatic activities recruitment by specific domains of TIF2 are involved in NF-kappaB transactivation]. / La actividad transcripcional de NF-kappaB es diferencialmente regulada por dominios específicos del coactivador TIF2.

We have previously shown that nuclear receptor coactivator overexpression significantly enhanced NF-kappaB activity in a dose response manner. We studied the mechanism by which TIF2 regulates NF-kappaB activity. We determined that: 1) the p38 specific inhibitor reduces 50% NF-kappaB transcriptional activity, even in cells that overexpress distinct TIF2 deletions; 2) there is a physical interaction between TIF2 and p38 and RelA determined through in vitro translated protein binding assays; 3) TIF2 is a p38 substrate; 4) there is a physical interaction between TIF2 and IKK in TNF-alpha 20 ng/ml stimulated or not HEK 293 cell protein extract, and IkappaB only in basal conditions, determined by binding pull down assays. This NF-kappaB complex regulates its activity and targets gene expression in a determined physiologic context depending on the coactivator complex content.