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.

Biosorption of bioactive compounds in bacterial nanocellulose: Mechanisms and physical-chemical properties.

Bacterial cellulose (BC) is a biomaterial produced by Gluconacetobacter xylinus, with wide applicability in different areas, such as biomedical, pharmaceutical, and food. BC production is usually carried out in a medium containing phenolic compounds (PC), such as teas, however, the purification process leads to the loss of such bioactive. Thus, the innovation of this research consists of the reincorporation of PC after the purification of the BC matrices through the biosorption process. In this context, the effects of the biosorption process in BC were evaluated to maximize the incorporation of phenolic compounds from a ternary mixture of hibiscus (Hibiscus sabdariffa), white tea (Camellia sinensis), and grape pomace (Vitis labrusca). The biosorbed membrane (BC-Bio) showed a great concentration of total phenolic compounds (TPC = 64.89 mg L-1) and high antioxidant capacity through different assays (FRAP: 130.7 mg L-1, DPPH: 83.4 mg L-1, ABTS: 158.6 mg L-1, TBARS: 234.2 mg L-1). The physical tests also indicated that the biosorbed membrane presented high water absorption capacity, thermal stability, low permeability to water vapor and improved mechanical properties compared to BC-control. These results indicated that the biosorption of phenolic compounds in BC efficiently increases bioactive content and improves physical membrane characteristics. Also, PC release in a buffered solution suggests that BC-Bio can be used as a polyphenol delivery system. Therefore, BC-Bio is a polymer with wide application in different industrial segments.

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.

Bioactive profile of edible nasturtium and rose flowers during simulated gastrointestinal digestion.

Rose and nasturtium are common ornamental edible flowers rich in phytochemicals whose application as food is not widely explored. The gastrointestinal environment can modify these compounds, resulting in new combinations with different bioactivity. This study aimed to evaluate the effects of simulated gastrointestinal digestion (SGD) on rose and nasturtium flower extracts. Using UPLC-HRMS, 38 phenolic compounds were identified, and the SGD caused significant changes, mainly in the glycosylated phenolic. Furthermore, antioxidant activity was correlated with the increase in the concentrations of some polyphenols. Tested Gram-negative bacteria showed sensitivity to the flower extracts; their growth was inhibited by up to 82.7%. SGD interrupted the bacterial growth inhibition power of the rose extracts. On the other hand, an increase in inhibition ranging from 52.25 to 54.72%was found for nasturtium extracts, correlated to the behavior of some bioactive. Hence, SGD resulted in significant changes in phenolic profiles of the edible flowers, increasing antioxidant activity and changing antimicrobial effects.

Biotechnological potential of fungi from a mangrove ecosystem: Enzymes, salt tolerance and decolorization of a real textile effluent.

The mangrove is an ecosystem bounded by the line of the largest tide in size that occurs in climatic and subtropical regions. In this environment, microorganisms and their enzymes are involved in a series of transformations and nutrient cycling. To evaluate the biotechnological potential of fungi from a mangrove ecosystem, samples from mangrove trees were collected at the Paranaguá Estuarine Complex in Brazil and 40 fungal isolates were obtained, cultivated, and screened for hydrolytic and ligninolytic enzymes production, adaptation to salinity and genetic diversity. The results showed a predominance of hydrolytic enzymes and fungal tolerance to ≤ 50 g L-1 sodium chloride (NaCl) concentration, a sign of adaptive halophilia. Through morphological and molecular analyses, the isolates were identified as: Trichoderma atroveride, Microsphaeropsis arundinis, Epicoccum sp., Trichoderma sp., Gliocladium sp., Geotrichum sp. and Cryphonectria sp. The ligninolytic enzymatic potential of the fungi was evaluated in liquid cultures in the presence and absence of seawater and the highest activity of laccase among isolates was observed in the presence of seawater with M. arundinis (LB07), which produced 1,037 U L-1. Enzymatic extracts of M. arundinis fixed at 100 U L-1 of laccase partially decolorized a real textile effluent in a reaction without pH adjustment and chemical mediators. Considering that mangrove fungi are still few explored, the results bring an important contribution to the knowledge about these microorganisms, as their ability to adapt to saline conditions, biodegradation of pollutants, and enzymatic potential, which make them promising candidates in biotechnological processes.

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.

Laccases as green and versatile biocatalysts: from lab to enzyme market-an overview.

Laccases are multi-copper oxidase enzymes that catalyze the oxidation of different compounds (phenolics and non-phenolics). The scientific literature on laccases is quite extensive, including many basic and applied research about the structure, functions, mechanism of action and a variety of biotechnological applications of these versatile enzymes. Laccases can be used in various industries/sectors, from the environmental field to the cosmetics industry, including food processing and the textile industry (dyes biodegradation and synthesis). Known as eco-friendly or green enzymes, the application of laccases in biocatalytic processes represents a promising sustainable alternative to conventional methods. Due to the advantages granted by enzyme immobilization, publications on immobilized laccases increased substantially in recent years. Many patents related to the use of laccases are available, however, the real industrial or environmental use of laccases is still challenged by cost-benefit, especially concerning the feasibility of producing this enzyme on a large scale. Although this is a compelling point and the enzyme market is heated, articles on the production and application of laccases usually neglect the economic assessment of the processes. In this review, we present a description of laccases structure and mechanisms of action including the different sources (fungi, bacteria, and plants) for laccases production and tools for laccases evolution and prediction of potential substrates. In addition, we both compare approaches for scaling-up processes with an emphasis on cost reduction and productivity and critically review several immobilization methods for laccases. Following the critical view on production and immobilization, we provide a set of applications for free and immobilized laccases based on articles published within the last five years and patents which may guide future strategies for laccase use and commercialization.

Antioxidant Properties of Lyophilized Rosemary and Sage Extracts and its Effect to Prevent Lipid Oxidation in Poultry Pátê.

This study aimed to evaluate the antioxidant activities (AA) of lyophilized rosemary extract and lyophilized sage extract, and their effects on the oxidative stability of poultry pátê. For this purpose, four poultry pátê formulations with rosemary, sage, sodium erythorbate and a control (without antioxidants) were produced. The rosemary and sage were characterized according to total phenolic compounds (TPC) and AA by several methods. The poultry pátês stored at 4 °C were evaluated by the lipid oxidation. High concentrations of TPC were detected in the rosemary extract and sage extract (46.48 and 41.61 mg GAE/g (Gallic acid equivalent), respectively). The AA of the rosemary and sage extracts determined by free radical-scavenging were 4745.72 and 2462.82 µmol TE/g (Trolox equivalents), respectively. The high concentrations of catechin, rutin, myricetin and p-coumaric acids in these extracts may be responsible for the strong inhibitory action against food pathogens. Besides this, these compounds can be responsible for the best performance in inhibiting lipid oxidation in poultry pátês during storage. This study suggests that rosemary and sage extracts may be used as a natural antioxidant in meat products.

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.

Bacterial cellulose: From production optimization to new applications.

Bacterial cellulose (BC) is a biopolymer of great significance to the medical, pharmaceutical, and food industries. However, a high concentration of carbon sources (mainly glucose) and other culture media components is usually required to promote a significant yield of BC, which increases the bioprocess cost. Thus, optimization strategies (conventional or statistical) have become relevant for the cost-effective production of bacterial cellulose. Additionally, this biopolymer may present new properties through modifications with exogenous compounds. The present review, explores and discusses recent studies (last five years) that report the optimization of BC production and its yield as well as in situ and ex situ modifications, resulting in improved mechanical, antioxidant, and antimicrobial properties of BC for new applications.

Solid-state fermentation with orange waste: optimization of Laccase production from Pleurotus pulmonarius CCB-20 and decolorization of synthetic dyes

Laccases are oxidoreductase enzymes that have the ability to oxidize phenolic substrates. Its biotechnological potential has been greatly explored in many areas as biotechnology industry, bioremediation of dyes, food industry and environmental microbiology. The aim of this study was maximize the laccase production by Pleurotus pulmonarius (Fr.) Quélet in solid-state fermentation (SSF) using orange waste as substrate. After optimization the capability of the crude laccase to decolorize dyes was analyzed. The fermentation medium in the solid-state was optimized by applying a factorial design. After statistics optimization, laccase activity increased two times. The laccase activity appears to be correlated with the ability of crude extract to decolorize some industrial dyes. The optimized laccase was characterized with respect to optimum pH, influence of temperature and salts. Our results demonstrate that P. pulmonarius was an efficient producer of an important industrial enzyme, laccase, in a cheap solid-state system using orange waste as substrate.

Improvement of phenolic compound bioaccessibility from yerba mate (Ilex paraguariensis) extracts after biosorption on Saccharomyces cerevisiae.

Great efforts have been made to increase the bioaccessibility of bioactive compounds from plant sources. This can be achieved by the innovative and effective method of biosorption of these compounds in Saccharomyces cerevisiae obtained from the industrial fermentative process (waste yeast). In this context, this research evaluated if chemical modifications of depleted yeast can improve the capacity to biosorb the phenolic compounds and if through in vitro digestion tests, this approach can increase bioaccessibility of the secondary metabolites from yerba mate. The results showed that the chemical modification of the yeast promoted an increase in the biosorption efficiency of the bioactive compounds. Mass spectrometry peaks for the phenolic compounds reduced after biosorption as observed for the caffeic and dicaffeoylquinic acids and for kaempferol and rutin. In addition, a 10% reduction of caffeine was verified after biosorption, quantified by mass spectrometry chromatography. This showing that the compounds were retained in the cells, which was also observed by an increase of cell turgidity with scanning electron microscopy (SEM). Mid-infrared spectroscopy showed that the major bands related to the components of the compounds increased proportionally after biosorption. Furthermore, an increase of bioaccessibility of the yerba mate bioactive compounds adsorbed in S. cerevisiae was verified when compared with the crude extract.

Multi-block analysis for the correlation of physico-chemical and rheological data of 42 fruit pulps.

The common dimension (ComDim) chemometric method for multi-block analysis and hierarchical cluster analysis (HCA) were used to evaluate the data obtained from the physico-chemical and rheological characterization of 42 commercial fruit pulps. The physico-chemical characteristics and the rheological behavior of the pulps were found to be considerably different. The Herschel-Bulkley equation was fit to the steady-state flow curves of the fruit pulps, and it was found to appropriately describe the materials, which showed a wide range of yield stresses. The soluble solids content and the yield stress were the main factors responsible for the sample discrimination in the multivariate statistical analysis. The ComDim model indicates that these parameters may have a direct correlation. Namely, the soluble solids amount can influence the viscosity, as demonstrated by the similar scores of the samples in both common components, and this corroborated with the HCA analysis. PRACTICAL APPLICATIONS: Fruit pulps can be used as raw materials in the food industry to obtain several products, such as nectars, jellies, ice creams, and juices, which can also be sold directly to consumers. To evaluate the technical and economic feasibility of those industrial processes, it is important to know the physico-chemical properties of the products. Therefore, in this study we attempt to correlate the physical-chemical and rheological data using a new statistical approach.

Multi-block analysis coupled with GC-FID and ATR-MIR for the evaluation of thermal degradation in vegetable oils.

The effect of heating in twenty-four different oil samples was evaluated via iodine value (IV), gas chromatography (GC) and mid-infrared (MIR) analyses. Common components and specific weights analysis (CCSWA) was applied to distribute the samples according to their most relevant characteristics, thereby revealing the influence of heating on composition. Instrumental analysis indicated a high amount of beneficial fatty acids, such as alpha-linolenic acid, in less exploited oils such as chia oil. This oil can present nutritional damage when subjected to high temperatures and is thus less recommended for frying. Conversely, oils containing high amounts of linoleic acid, such as almond and nut oils, as well as those containing equivalent amounts of alpha-linolenic and linoleic acids, such as golden flaxseed and flaxseed oils, displayed greater resistance to temperature. The 3008/cm band exhibited greater intensity in oils with a higher degree of unsaturation, such as chia and linseed oils, a phenomenon mainly influenced by the presence of linoleic and alpha-linolenic fatty acids. After heating, there was a decrease in the intensity of this band. The main parameter discriminating the tested oil samples based on CCSWA was the degree of unsaturation. Overall, the employed statistical method was effective in analyzing the data obtained via the applied techniques, revealing the influence of each assessed parameter.

Chemical modification of citrus pectin: Structural, physical and rheologial implications.

The present study aimed to investigate the physical, structural and rheological modifications caused by the chemical modification process of citrus pectin. Therefore, three commercial citrus pectins with different degree of esterification were chemically modified by sequential alkali and acidic hydrolytic process to produce modified citrus pectins (MCP) with special properties. The molar mass (Mw), degree of esterification (DE), monosaccharide composition, 13C NMR spectra, homogeneity, morphology (SEM) and rheological behavior of both native and modified citrus pectins (MCP) were investigated. The chemical modification reduced the acid uronic content (up to 28.3%) and molar mass (up to 29.98%), however, showed little influence on the degree of esterification of native pectins. Modified citrus pectins presented higher amounts of neutral monosaccharides, mainly galactose, arabinose and rhamnose, typical of the Ramnogalacturonana-I (RG-I) region. Rheological tests indicated that the native and modified citrus pectins presented pseudoplastic behavior, however, the MCP samples were less viscous, compared to the native ones. Modified samples presented better dissolution in water and less strong gels, with good stability during oscillatory shearing at 25°C. This study aims to better understand the implications that chemical modifications may impose on the structure of citrus pectins.

A comparative study of the capsaicinoid and phenolic contents and in vitro antioxidant activities of the peppers of the genus Capsicum: an application of chemometrics.

This paper presents a comparison of the contents of capsaicin, dihydrocapsaicin and total phenolics as well as of the antioxidant activities of six types of peppers of the genus Capsicum. The varieties were analyzed in terms of their in vitro antioxidant activity using ferric reducing antioxidant powder (FRAP), 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis 3-ethylbenzothiazoline 6-sulfonate (ABTS(●+)) assays. The contents of phenolics and capsainoids as well as the antioxidant activities were higher in seeds than in pulps. The correlations (ρ < 0.01) between the phenolic composition and the capsaicinoids levels were high (r = 0.98). Similarly high were also the correlations between the antioxidant activities and the contents of total phenolics and capsaicinoids. Data were analyzed using principal component analysis (PCA), hierarchical cluster analysis (HCA) and multiple linear regression (MLR). PCA explained 97.77 % of the total variance of the data, and their separation into three groups in a scatter plot was divised. Using HCA, three clusters were suggested. Cluster one, formed by pulps (bell pepper, orange habanero, cayenne, dedo de moça and red habanero), showed the lowest levels of the compounds quantified. Most seed samples were grouped in cluster two (bell pepper, cayenne, dedo de moça and malagueta) together with malagueta pulp. Cluster three was formed by orange and red habanero seeds, which showed the highest levels of all compounds analyzed. The MRL revealed that the values of capsaicinoids and total phenols are more adequate to predict the antioxidant activity measured by the FRAP assay.

Physicochemical properties of modified citrus pectins extracted from orange pomace.

Modified pectin is a polysaccharide rich in galacturonic acid altered by pH adjustment and thermal treatment used especially as an anti-cancer agent. The aim of this work was to study the physical and chemical properties of modified pectins extracted from orange pomace with citric and nitric acids. The galacturonic acid content, degree of esterification, Fourier Transform Infrared Spectroscopy profile, molecular weight, intrinsic viscosity, rheological properties and antioxidant activity of the pectins were evaluated. The modification process caused the de-esterification of pectins and a decrease of molecular weight due to removal of neutral sugars, maintaining the linear chain of galacturonic acid. Such changes also caused a significant increase in the in vitro antioxidant activity (p ≤ 0.05) and influenced the rheological properties of pectin, reducing its viscosity. This work showed that the modification of pectin from orange pomace with citric and nitric acids altered its structural and physical characteristics as well as its biological activity toward a free-radical.

Extraction and quantification of phenolic acids and flavonols from Eugenia pyriformis using different solvents.

The recovery of phenolic compounds of Eugenia pyriformis using different solvents was investigated in this study. The compounds were identified and quantified by reverse-phase high-performance liquid chromatography coupled with ultraviolet-visible diode-array detector (RP-HPLC-DAD/UV-vis). Absolute methanol was the most effective extraction agent of phenolic acids and flavonols (588.31 mg/Kg) from Eugenia pyriformis, although similar results (p ≤ 0.05) were observed using methanol/water (1:1 ratio). Our results clearly showed that higher contents of phenolic compounds were not obtained either with the most or the least polar solvents used. Several phenolic compounds were identified in the samples whereas gallic acid and quercetin were the major compounds recovered.