Chemical Constituents and Antioxidant Potential of Red Guava (Psidium cattleianum Sabine) from Southern Brazil in Different Edible Ripening Stages

Ripening and growing location are important factors that can impact fruit quality characteristics. In this study, the influence of these factors on physicochemical characteristics, carbohydrates, aliphatic organic acids, phenolic compounds, and antioxidant capacity of red guava (Psidium cattleianum Sabine) was evaluated. Fruit ripening increased fructose and glucose (up to 22.83 and 16.42 g 100 g- 1 dry matter (DM), respectively), and decreased citric acid, the major organic acid (up to 135.35 mg g- 1 DM). Ripening and growing location also influenced the concentration of phenolic compounds and antioxidant capacity of red guava, in which a dependency between both factors was observed in most cases. Apigenin, galangin, isoquercitrin, among other phenolic compounds were quantified for the first time in red guava, in which isoquercitrin was the major (up to 13409.81 mg kg- 1 DM). The antioxidant potential of red guava was also confirmed by ferric reducing antioxidant power assay (up to 82.63 µmol Fe+ 2 g- 1 DM), Folin-Ciocalteu reducing capacity assay (up to 17.79 mg gallic acid equivalent g- 1 DM), and DPPH free radical scavenging assay (up to 25.36 mg ascorbic acid equivalent g- 1 DM). These results especially demonstrated the bioactive potential of red guava and provided knowledge regarding the influence of ripening and growing location on chemical and bioactive components encouraging its industrial exploitation.

Free amino acid profile in Mimosa scabrella honeydew honey from Brazil and chemometric analysis for geographical discrimination

In this study, twenty free amino acids (FAA) were investigated in samples of bracatinga (Mimosa scabrella) honeydew honey (BHH) from Santa Catarina (n = 15) and Paraná (n = 13) states (Brazil), followed by chemometric analysis for geographic discrimination. The FAA determination was performed by gas chromatography-mass spectrometry (GC-MS) after using a commercial EZ:faast™ kits for GC. Eight FAA were determined, being proline, asparagine, aspartic and glutamic acids found in all BHH, with significant differences (p < 0.05). In addition, with the exception of proline, the others FAA (asparagine, aspartic and glutamic) normally showed higher concentrations in samples from Santa Catarina state, being that in these samples it was also observed higher FAA sums (963.41 to 2034.73 mg kg-1) when compared to samples from Paraná state. The variability in the results did not show a clear profile of similarity when the heatmap and hierarchical grouping were correlated with the geographic origin and the concentration of eight determined FAA. However, principal component analysis (PCA) demonstrated that serine, asparagine, glutamic acid, and tryptophan were responsible for the geographic discrimination among samples from Santa Catarina and Paraná states, since they were the dominant variables (r > 0.72) in the PCA. Therefore, these results could be useful for the characterization and authentication of BHH based on their FAA composition and geographic origin.

High acidity of bracatinga honeydew honey: A new regulatory limit proposal

The free acidity of bracatinga honeydew honey (BHH) was monthly monitored over short-term storage (four months) until all the samples exceeded 50 mEq kg-1 - the maximum value allowed by the international regulatory honey standards. In addition, BHH quality was also investigated through moisture content, water activity, electrical conductivity, pH, 5-hydroxymethylfurfural, and aliphatic organic acids (AOA) analyses. According to our results, most of the parameters investigated presented significant differences during the short storage period studied; however, the quality parameters (except acidity) did not exceed the limits established by the international regulatory honey standards. Therefore, the high free acidity observed in the BHH samples did not affect its quality. Moreover, the total AOA concentration decreased as the free acidity increased, indicating that the high acidity is not related to postharvest fermentation. Since all BHH samples exceeded the established limit of 50 mEq kg-1 after four months of storage (up to 62.7 mEq kg-1), this data corroborates that this type of honey does not comply with the regulatory honey standards, which represents an obstacle to its commercialization. Therefore, our data reinforce the need for a future reassessment of the international regulatory honey standards regarding the free acidity limit for BHH. In this sense, taking together all the studies developed by our research group since 2014, a new free acidity value of 65 mEq kg-1 is proposed, which may discourage fraud practices and negative impacts on the BHH beekeeping chain.

Effect of long-term and heating storage on honey visible spectrum: an alternative parameter for quality monitoring of bracatinga honeydew honey

Bracatinga (Mimosa scabrella Bentham) honeydew honey (BHH) is a peculiar Brazilian honey. It is produced only every 2 years, which raises concerns about its quality since it can be submitted to different storage conditions until a new harvest is carried out. Therefore, this study investigated the changes in the visible spectrophotometric profile (VSP) of BHH during its storage at room temperature over 24 months and 40 °C for 4 months. Our findings indicated a similar VSP between the BHH samples, but that varied according to the storage condition. These changes were associated with the formation of brown compounds, such as 5-hydroxymethylfurfural, which has a maximum limit established for honeys. Thereby, absorbance above 0.500 absorption units between 380 and 410 nm was proposed as indicative of BHH exposure to prolonged heating with significant loss of its quality. Still, a regression model for absorbance at 380 nm was proposed aiming to predict the BHH storage time at room temperature, since storage time longer than 20 months at average temperatures of 23.0 ± 2.3 °C do not seem to be suitable for BHH. Thus, the VSP showed potential for monitoring BHH quality.

Assessment of Sorbate and Benzoate Content in Mustard, Ketchup and Tomato Sauce by Sub-Minute Capillary Electrophoresis

Research background

Sorbate and benzoate are important preservatives in food products, but these compounds can also have genotoxic effects, causing health risks to consumers. In this regard, this study aims to determine the mass fractions of sorbate and benzoate in Brazilian samples of mustard, ketchup and tomato sauce using an adequately validated sub-minute capillary electrophoresis method.

Experimental approach

In this study, sorbate and benzoate were evaluated in sauce samples by capillary electrophoresis using a simple sample preparation procedure. Previously, the method was validated according to Eurachem guidelines, and its greenness was assessed by Eco-Scale.

Results and conclusions

The fitness for purpose of the method, as well as its suitability for the analysis of the studied matrices and its agreement with the principles of green chemistry were checked and confirmed. Also, according to our findings, among the 30 commercial samples assessed, six of them presented some mislabeling or non-compliance with European or Brazilian legislation, reinforcing the constant need for quality assessment and surveillance of food products.

Novelty and scientific contribution

So far, there have been few studies related to investigating the preservatives such as sorbate and benzoate in mustard, ketchup and tomato sauce, highlighting the significance and contribution of the obtained results to the knowledge in the field.

Physicochemical properties and biological activities of bracatinga honeydew honey from different geographical locations

Bracatinga (Mimosa scabrella Bentham) honeydew honey is a Brazilian dark honey in increasing international appreciation. In this sense, the knowledge of its composition and potential biological properties becomes indispensable. In the present study, the physicochemical characteristics, including mineral and phenolic composition, and the scavenging, reducing, and antimicrobial proprieties of bracatinga honeydew honey (bhh) from five different geographical locations, were investigated. Bhh proved to be a potential functional food due to its high content of minerals (up to 6395 mg kg^-1) and phenolic compounds (up to 2393 µg 100 g^-1) and high scavenging and reducing activities. High antimicrobial activity against four bacterial strains, with minimum inhibitory concentration values ranging from 10 to 60%, were also found. Additionally, through principal component analysis, partial discrimination of bhh was observed according to the geographical location, which favored the separation of samples from Lages, and mainly due to the presence of nectar in this honey, which was proposed for the samples from Bom Retiro.

SUPPLEMENTARY INFORMATION

The online version of this article (10.1007/s13197-020-04937-x) contains supplementary material, which is available to authorized users.

Quantification of pyrrolizidine alkaloids in Senecio brasiliensis, beehive pollen, and honey by LC-MS/MS

This article presents the determination of eight pyrrolizidine alkaloids (PAs) by LC-MS/MS in honeys, pollen, and Senecio brasiliensis (Asteraceae) samples, all from Santa Catarina state, Brazil. In addition, the Box-Behnken design was used to perform an optimized sample preparation on pollens and S. brasiliensis parts. Senecionine and its N-oxide, besides retrorsine N-oxide, were determined in six of the seven honeys samples. Pollen from species of the Asteraceae, Fabaceae, and Boraginaceae families were found with greater predominance in three of the seven honeys samples. In these three honeys samples were also found the highest PAs levels. In beehive pollen, flower, and leaf of S. brasiliensis, the total levels of PAs and their N-oxides reached 221, 14.1 × 10⁴, and 14.8 × 10⁴ mg kg^-1, respectively. In honeys, these compounds are chemical contaminants and therefore undesirable when the sum exceeds 71 µg kg^-1, according to EFSA. On the other hand, although PAs are naturally present in plant and pollen of some species (Senecio, Crotalaria, Bacharis, Ecchium, Mimosa scabrella, Vernonia), it is important to monitor their levels in plants but also in honeys, and other beehive products since these compounds are transferred to the final product.

Phenolic composition and biological activities of stingless bee honey: An overview based on its aglycone and glycoside compounds

Stingless bees are native to tropical and subtropical countries, such as Brazil. The wide variety of species, the sources of food collection (nectar and pollen), and the climate conditions strongly affect the chemical composition of the honey, making this a unique product with peculiar characteristics. Stingless bee honey presents higher water content, higher acidity, and a lower sugar concentration when compared to Apis mellifera honey. Moreover, there is a wide variety of microorganisms in stingless bees' environment, which leads their honey to go through a natural fermentative process during its production in the hive. Besides, fermentation and hydrolysis are effective ways to convert glycosides into aglycones, thus increasing the bioavailability of compounds. In this sense, stingless bee honey may possess a greater concentration of phenolic compounds aglycones than glycosides, which would increase its potential benefits. Therefore, this review aims to compile the most recent studies of stingless bee honey phenolic profile and its biological potential (antioxidant, antimicrobial, and anti-inflammatory activities) and a possible connection to its natural fermentation process.

Current status of the gastrointestinal digestion effects on honey: A comprehensive review

In the past five years, more than 8000 scientific reports have been published on honey composition and its potential bioactivity as a source of pro-health components. However, the potential effectiveness of nutrients and other compounds in the human body is greatly influenced by the individual digestion conditions. Consequently, changes in the structure of honey components and their interactions with other constituents are expected and they may affect the bioaccessibility, the bioavailability, and further physiological functions of honey nutrients and bioactives. In this context, in addition to present key physiological characteristics for each step of the human digestion and their simulation aspects, this review also summarizes and discusses available data regarding the effect of the digestion (in vitro and in vivo) on honey compounds. Additionally, we consider the influence of the digestion on biological activities described for the compounds in the honey.

Quality, composition and health-protective properties of citrus honey: A review

Citrus honey is one of the most important monofloral honeys produced and consumed worldwide. This honey has pleasant sensorial characteristics, which include light color and typical aroma and flavor. Besides that, several constituents such as minerals, phenolic and volatile compounds, amino acids, sugars, enzymes, vitamins, methylglyoxal and organic acids are found in citrus honey. Moreover, potential biological properties have been associated with citrus honey. All these factors make it highly desired by consumers, increasing its market value, which can stimulates the practice of fraud. Also, citrus honey is susceptible to contamination and to inadequate processing. All these factors can compromise the quality, safety and authenticity of citrus honey. In this sense, this review aims to update and to discuss, for the first time, the data available in the literature about the physicochemical and the sensorial characteristics, composition, health properties, contamination, authenticity and adulteration of citrus honey. With this background, we aim to provide data that can guide future researches related to this honey.

Comparative quantification and differentiation of bracatinga (Mimosa scabrella Bentham) honeydew honey proteins using targeted peptide markers identified by high-resolution mass spectrometry

Honey traceability is an important topic, especially for honeydew honeys, due to the increased incidence of adulteration. This study aimed to establish specific markers to quantify proteins in honey. A proteomics strategy to identify marker peptides from bracatinga honeydew honey was therefore developed. The proteomics approach was based on initial untargeted identification of honey proteins and peptides by LC-ESI-Triple-TOF-MS/MS, which identified the major royal jelly proteins (MRJP) presence. Afterwards, the peptides were selected by the in silico digestion. The marker peptides were quantified by the developed targeted LC-QqQ-MS/MS method, which provided good linearity and specificity, besides recoveries between 92 and 100% to quantify peptides from bracatinga honeydew honey. The uniqueness and high response in mass spectrometry were backed by further complementary protein analysis (SDS-PAGE). The selected marker peptides EALPHVPIFDR (MRJP 1), ILGANVK (MRJP 2), TFVTIER (MRJP 3), QNIDVVAR (MRJP 4), FINNDYNFNEVNFR (MRJP 5) and LLQPYPDWSWTK (MRJP 7), quantified by LC-QqQ-MS/MS, highlighted that the content of QNIDVVAR from MRJP 4 could be used to differentiate bracatinga honeydew honey from floral honeys (p < 0.05) as a potential marker for its authentication. Finally, principal components analysis highlighted the QNIDVVAR content as a good descriptor of the analyzed bracatinga honeydew honey samples.

In vitro anti-inflammatory properties of honey flavonoids: A review

Honey is a natural ready-to-eat product rich in flavonoids, which is known by the wound healing properties due to both antibacterial and antioxidant activity. Flavonoids mitigate inflammatory processes, and thus it could currently support studies of anti-inflammatory potential of honeys. In this review, in vitro anti-inflammatory properties of flavonoids found in honey were prioritized. Mechanistic information of specific isolated flavonoids as modulators of inflammatory processes are summarized aiming to stimulate studies regarding the action of honey in inflammatory events. Lastly, a structure-activity relationship (SAR) of flavonoids was also included. Flavonoids found in honey have demonstrated antioxidant properties and ability to inhibit pro-inflammatory enzymes such as COX, LOX, iNOS, and pro-inflammatory mediators, including nitric oxide, cytokines and chemokines. Transcriptional factors such as NF-κB are also modulated by flavonoids, controlling the expression of several inflammatory mediators. SAR studies demonstrate the effect of flavonoids in the prevention of inflammatory cascades. Despite the promising reports of in vitro anti-inflammatory activity, well-designed clinical trials need yet to be performed to confirm the benefits of honeys from different botanical sources in diseases that include episodes of inflammation.

Aliphatic organic acids as promising authenticity markers of bracatinga honeydew honey

This study aimed to differentiate bracatinga (Mimosa scabrella Bentham) honeydew honey (BHH) from blossom honeys and BHH intentionally adulterated, all of them from three harvests, associating data of aliphatic organic acids (AOA) determined by capillary electrophoresis and chemometric analyses. The profile and concentration of AOA in pure BHH were similar between harvests, but distinct from blossom honeys. Succinic, glycolic, glutaric, malic, acetic, gluconic, and lactic acids were responsible for the differentiation between these two types of honey since they were the dominant variables (r > 0.80) in the principal component analysis. Based on this, the classification and regression trees method was used to develop a classification model considering these AOA. The proposed method needed only six of these AOA and adequately classified all blossom honeys and almost all pure and adulterated BHH. Therefore, the proposed model proved to be promising and reliable for verifying authenticity and fraud detection in BHH.

Pyrrolizidine alkaloids and beehive products: A review

Pyrrolizidine alkaloids (PA) are secondary metabolites of plants, which are mostly found in the genus Senecio, Echium, Crotalaria, and Eupatorium. The presence of 1,2-unsaturated PA in foods is a concern to food regulators around the world because these compounds have been associated to acute and chronic toxicity, mainly in the liver. The intake foods with PA/PANO usually occur through accidental ingestion of plants and their derivatives, besides to products of vegetal-animal origin, such as honey. PA/PANO are transferred to honey by their presence in nectar, honeydew, and pollen, which are collected from the flora by bees. In addition to honey, other beekeeping products, such as pollen, royal jelly, propolis, and beeswax, are also vulnerable to PA contamination. In this context, this review provides information about chemical characteristics, regulation, and toxicity, as well as summarizes and critically discusses scientific publications that evaluated PA in honeys, pollens, royal jelly, and propolis.

Use of visible spectrophotometric fingerprint and chemometric approaches for the differentiation of Mimosa scabrella Bentham honeydew honey

Honeydew honeys, including bracatinga (Mimosa scabrella Bentham) honeydew honey, are highly appreciated due to its nutritional and sensory properties. Therefore, fast and inexpensive methods must be developed to differentiate this distinct class of honey. Although methods using the visible spectrophotometric fingerprint (VSF) have never been used to differentiate bracatinga honeydew honey and blossom honey, this technique appears to be a viable alternative, successfully used in the differentiation and fraud detection of various foods, including honeys from other botanical sources. In this sense, the present study aimed to verify the existence of a specific VSF for bracatinga honeydew honey and blossom honey and differentiate both type of honeys using the VSF associated with chemometric analysis. The VSF of 30 bracatinga honeydew honeys harvested in three different years (2014, 2016, and 2018) and 21 blossom honeys (harvested in 2016) were evaluated. The existence of a different VSF for bracatinga honeydew honeys and blossom honeys allowed the satisfactory differentiation of both types of honeys. Additionally, bracatinga honeydew honey presented a unique VSF, independent of the year of harvest, which can be exploited as a fingerprint of this type of honey, contributing to its authenticity.

Determination of Phenolic Compounds in Three Edible Ripening Stages of Yellow Guava (Psidium cattleianum Sabine) after Acidic Hydrolysis by LC-MS/MS

Yellow guava (Psidium cattleianum Sabine) has received considerable attention in the last years because of their high content in bioactive compounds with potential application in food and pharmaceutical industries. In this regard, this study aimed to investigate the phenolic compounds of three edible ripening stages of yellow guava fruits after acidic hydrolysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and their antioxidant capacity. Among the 23 phenolics quantified, catechin, isoquercitrin, quercetin, gallic acid, and syringic acid showed significant concentrations in all the evaluated stages, with values ranging from 479.59 ± 12.52 to 12,795.50 ± 320.95 μg 100 g^-1 of dry matter. In general, higher concentrations of phenolic acids were found in the latter ripening stages, while flavonoids were in the earlier ripening stages. These findings suggest that the ripening process promotes changes in the phenolic composition of yellow guava. However, considering the sum of phenolic compounds and the antioxidant capacity, all ripening stages investigated can be suggested as a supply of bioactive compounds for consumers.

Dataset about Southern-Brazilian geopropolis: Physical and chemical perspectives

The dataset showed in this manuscript belongs to the investigation of the Southern-Brazilian geopropolis of stingless bees. Stingless bees are native species of insects from tropical areas; they produce honey, pollen and geopropolis that is composed of a mix of vegetal extracts, digestive enzymes, and mostly by soil. Used in folk medicine as antiseptic, antioxidant and antimicrobial agent, the composition is due to bee species, climate changes, local flora, and soil type. Moreover, the complex chemical content gives to the geopropolis a bioactive potential, with scavenging characteristics that is important to avoid free radical damages in the human health.

Regarding the importance of exploring new natural matrices sources with bioactive potential, the first approach of chemical characterization of geopropolis is indispensable. Thus, ten samples of Southern-Brazilian geopropolis were analyzed and the bioactive responses obtained were discussed in the accompanying article titled “Southern-Brazilian geopropolis: A potential source of polyphenolic compounds and assessment of mineral composition”. Furthermore, the physicochemical analysis of moisture and ash content, the yield of extraction, the reducing activity and free radical scavenging potential of ethanolic extracts, the antimicrobial activity, and the analysis of HPLC-ESI-MS/MS chromatograms are the main data presented in brief. The data can guide scientists in order to know methods and data for these samples.

Southern-Brazilian geopropolis: A potential source of polyphenolic compounds and assessment of mineral composition

Geopropolis is a stingless bee product compose mainly by soil, presenting complex composition geopropolis has bioactive compounds that will depend on geographical characteristics as well bee species, changing their chemical and biological properties. Thus the study aims to evaluate the solubility and chemical stability of geopropolis extracts, through radical capture capacity and reducing capacity. Besides, analysis of free and bonded phenolic compounds, and mineral composition. Geopropolis samples of Melipona mondury, Melipona quadrifasciata, Melipona scutellaris, Melipona seminigra and Tetragonisca angustula were analyzed. Both reducing compounds with a maximum of 2.96% GAE and free radical scavenging potential with a maximum of 5.84% AAE and 8.58% TE increases over 30 days of storage time. Also, methanolic extracts released at least 51% more reducing compounds and exhibited at least 27% more free radical scavenging potential in comparison to ethanolic extracts. The polyphenolic profile shows 31 compounds after acid and alkaline hydrolysis as cinnamic acid, ferulic acid, p-coumaric acid, aromadendrin, vanillin. For the mineral composition, sixteen minerals were found among essential and non-essential, differentiating each sample by chemometric PCA and HCA analysis according to geographic region. Geopropolis is a potential source of natural compounds that could enhance food quality, increasing the bioactive content and preventing oxygen damages in foods, likewise for pharmacological application for healthcare.

Differentiation of honeydew honeys and blossom honeys: a new model based on colour parameters

The present study aimed to differentiate Mimosa scabrella Bentham (bracatinga) honeydew honeys from blossom honeys, with and without addition of heat treatment, and bracatinga honeydew honeys adulterated with blossom honeys (5, 15 and 25% of blossom honeys), using chromatic characterization associated with chemometric analysis. Bracatinga honeydew honeys presented unusual chromatic characteristics which allowed differentiation of blossom honeys by principal components analysis. Additionally, a classification model was developed in order to establish clear rules that characterize each group of honey. The proposed model correctly classified bracatinga honeydew honey and blossom honey samples, with and without heat treatment. Only two samples adulterated with 5% blossom honey were misclassified. The chromatic analysis associated with chemometric analysis showed promising perspectives for its exploitation being able to be used for screening and selection of bracatinga honeydew honey, fresh or thermally treated as well as fraud detection.

Neuroprotective effect of juçara (Euterpe edulis Martius) fruits extracts against glutamate-induced oxytosis in HT22 hippocampal cells

This study investigated the neuroprotective effect of juçara fruit extracts against glutamate-induced oxytosis in HT22 cells. Potential relationships between the extracts' polyphenolic composition and their protective/antioxidant capacities were also investigated. Experiments with the addition of either the crude methanolic extract or hexane, dichloromethane, ethyl acetate and butanol fractions 24 h before glutamate (pretreatment) and together with glutamate (co-treatment) were performed. At the concentration of 10 μg ml^-1, the hexane and dichloromethane fractions were able to protect cells, both in pretreatment and co-treatment. These fractions presented the highest number of quantified polyphenolics (24 and 21, respectively) although the total levels were 63-fold higher in the dichloromethane fraction. Syringaldehyde, vanillin and 4-aminobenzoic, cinnamic, salicylic and syringic acids were found only in these fractions. The dichloromethane fraction presented higher 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity, while the butanol and ethyl acetate fractions showed higher ferric reducing antioxidant power. These results suggest juçara fruits extracts as promising for the reduction of the risk of neurodegenerative diseases.

An overview of physicochemical characteristics and health-promoting properties of honeydew honey

Honeydew honey has differentiated chemical and physicochemical characteristics besides potential functional properties such as antimicrobial, anti-inflammatory and antioxidant. In this sense, the interest and consumption of this honey as a functional product by the food industry and consumers have increased. Honeydew honeys usually present dark color, a lower content of monosaccharides and higher values of pH, acidity, electric conductivity, proteins, minerals, phenolic compounds, and oligosaccharides compared to blossom honeys, which contribute to its outstanding biological activities. Consequently, contaminations and adulterations of this honey can occur and compromise the quality, safety and authenticity of honeydew honey. Thus, detailed knowledge of the composition and properties of honeydew honeys is of great importance, especially considering that honeydew honeys are still few studied and therefore underestimated. Therefore, in this review, the physicochemical characteristics, chemical and bioactive composition, functional and health-promoting properties of honeydew honey as well as contamination, adulteration and authenticity of this honey are summarized.

Blackberry (Rubus ulmifolius Schott): Chemical composition, phenolic compounds and antioxidant capacity in two edible stages

The berries of the genus Rubus has been highlighted as important source of bioactive and health promoting constituents, however, information about chemical composition and antioxidant potential of the specie Rubus ulmifolius are still scarce. In this regard, this study aimed to assess the physicochemical characteristics, total monomeric anthocyanins (TMA), individual phenolics, minerals, sugars, and antioxidant properties of mature and fully mature R. ulmifolius. With the advance of maturation, changes in the physicochemical composition suggest pleasant characteristics for consumption especially in the fully mature stage. High levels of TMA and sugars (fructose and glucose) were also verified in the fully mature stage, as well as, expressive antioxidant potential, with values of 241.06 μM Fe⁺² g^-1 for ferric reducing antioxidant power and 28.22 mg gallic acid equivalent g^-1 for Folin-Ciocalteu reducing capacity (all expressed in dry matter, DM). In contrast, minerals (potassium, calcium, sodium) and most of the studied phenolic compounds showed the highest concentrations in mature fruits. Among the phenolics investigated, 26 compounds were identified and quercetin and isoquercitrin were the predominant phenolic compounds in the fruit. The results reinforce the nutritive and antioxidant potential of Rubus ulmifolius in both maturation stages studied.

Phenolic Compounds Determined by LC-MS/MS and In Vitro Antioxidant Capacity of Brazilian Fruits in Two Edible Ripening Stages

The aim of this study was to investigate the free individual phenolics and the in vitro antioxidant capacity of blackberry, acerola, yellow guava, guabiju, jambolan and jabuticaba fruits in two edible stages. Of the thirty-three phenolics investigated by liquid chromatography - tandem mass spectrometry (LC-MS/MS), twenty-five were quantified and the major ones were catechin, isoquercitrin, epicatechin and gallic acid. The highest values for the total phenolic content (in dry matter) were observed for acerola (83.6 to 97.7 mg gallic acid equivalents g^-1 DM) and blackberry (18.9 to 28.3 mg gallic acid equivalents g^-1 DM); however, acerola, jabuticaba, and blackberry showed the highest antioxidant capacities (134.6 to 1120.4 mg Trolox equivalents g^-1 for 2,2-diphenyl-1-picrylhydrazyl and 43.6 to 501.8 μmol Trolox equivalents g^-1 for ferric reducing antioxidant power). For most fruits, the antioxidant capacity decreased during the ripening, possibly due to a decrease in the concentration of most of the phenolics.

Physicochemical characteristics of bracatinga honeydew honey and blossom honey produced in the state of Santa Catarina: An approach to honey differentiation

Due to the increasing demand and interest of the consumers of bracatinga honeydew honey, it becomes important to know its characteristics in order to guarantee the quality of this dark honey. It is also necessary to investigate possible parameters that easily determine their differentiation from other honeys, thus guaranteeing their authenticity. Therefore, in the present study, the physicochemical characteristics and the reducing/scavenging proprieties of 16 bracatinga (Mimosa scabrella Bentham) honeydew honey samples and 25 blossom honey (different botanical origin) samples from Santa Catarina, Brazil, were investigated. Bracatinga honeydew honeys were defined by its high free acidity, electrical conductivity and reducing/scavenging capacity, and low glucose content.Still, these specific parameters allowed the differentiation between bracatinga honeydew honeys and blossom honeys, from the of principal component analysis, contributing to the differentiation of these honeys.

Effect of in vitro gastrointestinal digestion on the bioaccessibility of phenolic compounds, minerals, and antioxidant capacity of Mimosa scabrella Bentham honeydew honeys

Honey is a product traditionally consumed due to its possible health benefits promoted by natural antioxidants. However, few studies have evaluated the effect of in vitro gastrointestinal digestion on these compounds in honeys. To improve the knowledge of this subject, the present study aimed to investigate the influence of simulated digestion on the stability of antioxidant capacity (FRAP, DPPH, and Folin-Ciocalteu assays), phenolic compounds (LC-ESI-MS/MS), and minerals (CE-DAD) in Mimosa scabrella Bentham honeydew honeys. The results show that the digestive system, mainly after duodenal digestion, significantly decreased the antioxidant capacity assessed by FRAP (410.3±18.3 to 564.7±8.4μmolFe⁺²100g^-1), DPPH (30.1±0.8 to 33.9±1.4mgAAE100g^-1), and Folin-Ciocalteu assays (58.3±2.6 to 142.0±1.6mgGAE100g^-1) of this honey. However, phenolic compounds and minerals showed high stability and in some cases, significantly increased after the simulated digestion, presenting a bioaccessible fraction that ranged from 78.2±6.4 to 174.38±6.82% and 94.0±4.3 to 220.5±3.4%, respectively. Therefore, these honey constituents may be considered highly bioaccessible and potentially bioavailable. Additionally, the correlation between the investigated parameters suggests that other honey constituents could also possibly affect antioxidant capacity of this honey. In conclusion, the bracatinga (Mimosa scabrella Benth.) honeydew honey can be highlighted as an important natural source of bioaccessible polyphenols, besides presenting highly bioaccessible minerals in its composition, maintaining a satisfactory antioxidant capacity.

Qualidade do preparado para bebida obtido a partir de polpa de juçara submetida ao tratamento térmico

Resumo As palmeiras do gênero Euterpe têm notável importância econômica e cultural, sendo que o seu valor se deve em parte às inúmeras formas de utilização, dentre as quais se destacam o consumo da bebida proveniente dos frutos e do palmito. Este estudo tem por objetivo avaliar a eficiência do tratamento térmico prévio nos frutos de juçara (E. edulis Martius) utilizados para o processamento da polpa de juçara, visando à obtenção de um preparado para bebida, com qualidade nutricional e segura para o consumo. Os frutos foram selecionados, higienizados com hipoclorito de sódio (200 ppm/15 min) e submetidos a três tratamentos térmicos (100 °C/5 s, 80 °C/10 s e 80 °C/30 s). Depois do tratamento foram realizados o despolpamento e o congelamento, seguidos de armazenamento. Os resultados das análises microbiológicas demonstram que é necessário o tratamento térmico a 100 °C/5 s para atender aos parâmetros microbiológicos exigidos pela legislação para polpa de açaí, além de preservar o conteúdo de antocianinas totais e atividade antioxidante. Desta forma, o tratamento térmico dos frutos apresenta-se como um método viável e de baixo custo, contribuindo para a produção da bebida com qualidade e segurança.

5-HMF and carbohydrates content in stingless bee honey by CE before and after thermal treatment

This study aimed to assess 5-hydroximethylfurfural and carbohydrates (fructose, glucose, and sucrose) in 13 stingless bee honey samples before and after thermal treatment using a capillary electrophoresis method. The methods were validated for the parameters of linearity, matrix effects, precision, and accuracy. A factorial design was implemented to determine optimal thermal treatment conditions and then verify the postprocedural 5-HMF formation, but once 5-HMF were <LOQ was not possible to build a response surface. The methods applied to samples obtained from Brazil, expressed good linearity, precision, and accuracy. None of the thirteen in natura samples presented 5-HMF, and carbohydrate levels ranged from 48.59% to 69.36%. In the same conditions of thermal treatment, Apis mellifera honey presented higher 5-HMF content than stingless bee honey. Results suggest that a high temperature related to briefer thermal treatment could be an efficient way to extend shelf life without affecting 5-HMF content in stingless bee honey.