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This study aimed to characterize and evaluate the in vitro bioactive properties of green banana pulp (GBPF), peel (GBPeF), and mixed pulp/peel flours M1 (90/10) and M2 (80/20). Lipid concentration was higher in GBPeF (7.53%), as were the levels of free and bound phenolics (577 and 653.1 mg GAE/100 g, respectively), whereas the resistant starch content was higher in GBPF (44.11%). Incorporating up to 20% GBPeF into the mixed flour had a minor effect on the starch pasting properties of GBPF. GBPeF featured rutin and trans-ferulic acid as the predominant free and bound phenolic compounds, respectively. GBPF presented different major free phenolics, though it had similar bound phenolics to GBPeF. Both M1 and M2 demonstrated a reduction in intracellular reactive oxygen species (ROS) generation. Consequently, this study validates the potential of green banana mixed flour, containing up to 20% GBPeF, for developing healthy foods and reducing post-harvest losses.

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The search for knowledge related to the Pitaya (Hylocereus polyrhizus [F.A.C. Weber] Britton & Rose, family Cactaceae) is commonly due to its beneficial health properties e aesthetic values. But process to obtain pitaya pulp is a first and important step in providing information for the subsequent use of this fruit as colorant, for example. Therefore, the effects of the pulping process on the metabolomic and chemometric profile of non-volatile compounds of pitaya were assessed for the first time. The differences in metabolic fingerprints using UPLC-QTOF-MSE and multivariate modeling (PCA and OPLS-DA) was performed in the following treatments: treatment A, which consists of pelled pitaya and no ascorbic acid addition during pulping; treatment B, use of unpelled pitaya added of ascorbic acid during pulping; and control, unpelled pitaya and no ascorbic acid addition during pulping. For the metabolomic analysis, UPLC-QTOF-MSE shows an efficient method for the simultaneous determination of 35 non-volatile pitaya metabolites, including isorhamnetin glucosyl rhamnosyl isomers, phyllocactin isomers, 2'-O-apiosyl-phylocactin and 4'-O-malonyl-betanin. In addition, the chemometric analysis efficiently distinguished the metabolic compounds of each treatment applied and shows that the use of unpelled pitaya added of ascorbic acid during pulping has an interesting chemical profile due to the preservation or formation of compounds, such as those derived from betalain, and higher yields, which is desirable for the food industry.

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The objective of this study was to determine the trace element composition and the toxic metal residues in Galician cow's milk cheese produced in different systems (artisan, industrial, and organic). Fourteen elements (As, Cd, Co, Cr, Cu, Fe, Hg, I, Mn, Mo, Ni, Pb, Se, and Zn) were determined in 58 representative samples of Galician cheeses by inductively coupled plasma mass spectrometry. The toxic elements were present at low concentrations, similar to those reported for other unpolluted geographical areas. The essential elements were also within the normal range in cheeses. There were no statistically significant differences between smoked and unsmoked cheeses for any of the elements. Chemometric analyses (principal component analysis and cluster analysis) revealed that the industrial cheeses produced in Galicia using the milk from intensive dairy farms were different, in terms of elemental content, from artisan and organic cheeses, in which the elemental contents were similar.

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The aim of the present study was to evaluate the sensory acceptability limit of refrigerated fish through a multivariate approach, involving classic physicochemical and bacteriological indicators and considering different consumer profiles. The results of the survival analysis demonstrated that, in general, consumers still considered the fish to be suitable for purchase (4.128 days of storage), despite being microbiologically unsuitable for consumption. However, the subsequent division of consumers into clusters indicated that women and individuals with high income and education levels tend to reject fish with few days of storage (3.650 days), mainly due to discoloration, despite still being microbiologically suitable for consumption. Thus, these segments present a safer behavior regarding the purchase of fresh fish. The influence of different frequencies of fish consumption and age of consumers on the assessment of fish freshness was not clarified. The responsibility for ensuring safe and healthy products at the point of sale must lie with the producers and distributors. However, improving consumers' ability to make good choices when buying fresh fish would bring social and economic benefits related to public health and to the seafood industry, because it would enable them to make relevant claims and demand their rights.

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A new method based on Ultraviolet spectrophotometry was developed and compared with that based on high-performance liquid chromatography for the determination and quantification of anthraquinones in the extracts of Rhamnus purshiana bark. A validated quantitative analysis of cascaroside A, cascaroside B, emodin, and aloe-emodin in these herbal products has been previously performed using high-performance liquid chromatography coupled with a diode array detector. In the high-performance liquid chromatography analysis, all the anthraquinones showed satisfactory regression (r2 > 0.98) within the test ranges, and the recovery was in the range of 94-117%. The limits of detection and quantification were 0.008-0.010 and 0.029-0.035 µg/mL, respectively. Hierarchical cluster analysis and principal component analysis showed differences in the anthraquinones determined from herbal samples. Subsequently, a simple and low-cost ultraviolet spectrophotometric methodology for the quantitative analysis of the same compounds in the extracts was applied, and all the contents were determined. A paired t-test confirmed that there were no significant differences between the two methods. Our results revealed that the developed method is simple and provides the ability to discriminate and control the quality of anthraquinones in herbal products.

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Preterm newborns are extremely vulnerable to morbidities, complications, and death. Preterm birth is a global public health problem due to its socioeconomic burden. Nurturing preterm newborns is a critical medical issue because they have limited nutrient stores and it is difficult to establish enteral feeding, which leads to inadequate growth frequently associated with poor neurodevelopmental outcomes. Parenteral nutrition (PN) provides nutrients to preterm newborns, but its biochemical effects are not completely known. To study the effect of PN treatment on preterm newborns, an untargeted metabolomic 1H nuclear magnetic resonance (NMR) assay was performed on 107 urine samples from 34 hospitalized patients. Multivariate data (Principal Component Analysis, PCA, Orthogonal partial least squares discriminant analysis OPLS-DA, parallel factor analysis PARAFAC-2) and univariate analyses were used to identify the association of specific spectral data with different nutritional types (NTs) and gestational ages. Our results revealed changes in the metabolic profile related to the NT, with the tricarboxylic acid cycle and galactose metabolic pathways being the most impacted pathways. Low citrate and succinate levels, despite higher glucose relative urinary concentrations, seem to constitute the metabolic profile found in the studied critically ill preterm newborns who received PN, indicating an energetic dysfunction that must be taken into account for better nutritional management.

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Calea pinnatifida (R. Br.) Less. is a plant of Brazilian folk medicine. We evaluated the influence of environmental factors on the chemical profile of C. pinnatifida collected during the winter season. C. pinnatifida leaves, alongside soil samples, were collected from two sites of different altitude. Plant samples were sequentially extracted, while soil samples were subject to compositional analysis. Plant extracts were compared using HPTLC-UV, using chemometric analyses to compare samplings harvested at both altitudes. Two marker metabolites, calein A (1) and acetylportentol (2), were isolated from samples collected at the respective altitudes. The differing metabolic profiles observed may be a result of the influence of environmental factors.

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INTRODUCTION: Praxelis genus comprises 24 species, however, only two species of this genus have been chemically investigated. Here we investigated Praxelis sanctopaulensis, a native plant from Brazil, that occurs mainly in Cerrado regions. OBJECTIVE: The goal was to identify the specialised metabolites from P. sanctopaulensis, and compare with those described from Praxelis and Chromolaena species. METHODS: The phytochemical study of P. sanctopaulensis was performed through different chromatography techniques, including high-performance liquid chromatography (HPLC), gas chromatography flame ionisation detector (GC-FID), and ultra-high-performance liquid chromatography high-resolution tandem mass spectrometry (UHPLC-HRMS/MS). The structures of the compounds were established based on spectroscopic analysis, total correlated spectroscopy (TOCSY), hydrogen decoupling and computational calculations was used to an unequivocal structural elucidation of a new sesquiterpene. The antioxidant activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP), and antimicrobial assay was performed by the microdilution method. Comparison of the flavonoids described P. sanctopaulensis was carried out using principal component analysis. RESULTS: The phytochemical investigation of P. sanctopaulensis led to the isolation of a pair of diastereomers, praxilone A and praxilone B. Seven known compounds were isolated from this species, another 14 fatty acids were detected in hexane fraction, and 26 compounds were identified from ethyl acetate fraction. All these compounds are being described for the first time in this species, with the exception of viridifloric acid. The ethyl acetate fraction showed potent antioxidant activity. CONCLUSIONS: Forty-seven compounds are described from P. sanctopaulensis. The combination of different techniques of nuclear magnetic resonance (NMR) spectroscopy and computational calculations allowed the unequivocal structure elucidation of a new cadinene. The clustering analysis showed similarities between the flavonoids identified in P. sanctopaulensis and in Chromolaena species.

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Tea is one of the most important beverages worldwide, is produced in several distinct geographical regions, and is traded on the global market. The ability to determine the geographical origin of tea products helps to ensure authenticity and traceability. This paper reviews the recent research on authentication of tea using a combination of instrumental and chemometric methods. To determine the production region of a tea sample, instrumental methods based on analyzing isotope and mineral element contents are suitable because they are less affected by tea variety and processing methods. Chemometric analysis has proven to be a valuable method to identify tea. Principal component analysis (PCA) and linear discriminant analysis (LDA) are the most preferred methods for processing large amounts of data obtained through instrumental component analysis.

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Tejocote (Crataegus mexicana, Mexican hawthorn), known as a weight-loss supplement, has been marketed online and is easily available for overseas direct purchase. Alipotec (brand name) is known as one of the most popular products containing tejocote in Mexico and other countries. However, adverse effects have been reported by users of these supplements. Therefore it is necessary to find the reason for the side effect. Dietary supplement samples labelled as containing tejocote were analysed using mass spectrometry and DNA barcoding analysis. Our results demonstrate that Alipotec samples contained ingredients from different species, yellow oleander instead of tejocote. The rpoB barcode region was able to differentiate between tejocote and yellow oleander species. Moreover, it was also observed that three compounds, including thevetin B, neriifolin, and digitoxigenin, clearly distinguish between tejocote and yellow oleander samples. This is the first and preliminary investigation to use an integrated approach of both chemical and genomic profiling for the authentication of dietary supplement containing tejocote.

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A variety of methods for producing cassava flour exist, resulting in very heterogeneous products that exhibit various colours, textures, granulometries, and flavours. To improve its attractiveness to consumers, some producers dye cassava flour with turmeric or tartrazine; however, this practice is illegal in Brazil. In this study, cassava flour samples were collected and evaluated for possible adulteration by the addition of dyes. Flours were analysed by CIELab and dye screening (paper chromatography and the turmeric-identification method) and a classification tree was developed using these data. Positive results for curcuminoid pigments or tartrazine were confirmed by HPLC-DAD or HPLC-UV-Vis, respectively. The developed approach is an innovative alternative chemometric-analysis method that facilitates highly practical screening; adulterated cassava flour, a product of great human-food importance, can be identified using CIELab parameters.

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The objective of this study was to investigate structural changes and lignin redistribution in Eucalyptus globulus pre-treated by steam explosion under different degrees of severity (S0), in order to evaluate their effect on cellulose accessibility by enzymatic hydrolysis. Approximately 87.7% to 98.5% of original glucans were retained in the pre-treated material. Glucose yields after the enzymatic hydrolysis of pre-treated material improved from 19.4% to 85.1% when S0 was increased from 8.53 to 10.42. One of the main reasons for the increase in glucose yield was the redistribution of lignin as micro-particles were deposited on the surface and interior of the fibre cell wall. This information was confirmed by laser scanning confocal fluorescence and FT-IR imaging; these microscopic techniques show changes in the physical and chemical characteristics of pre-treated fibres. In addition, the results allowed the construction of an explanatory model for microscale understanding of the enzymatic accessibility mechanism in the pre-treated lignocellulose.

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Berberis laurina (Berberidaceae) is a well-known medicinal plant used in traditional medicine since ancient times; however, it is scarcely studied to a large-scale fingerprint. This work presents a broad-range fingerprints determination through high-resolution magical angle spinning (HR-MAS) nuclear magnetic resonance (NMR) spectroscopy, a well-established flexible analytical method and one of most powerful "omics" platforms. It had been intended to describe a large range of chemical compositions in all plant parts. Beyond that, HR-MAS NMR allowed the direct investigation of botanical material (leaves, stems, and roots) in their natural, unaltered states, preventing molecular changes. The study revealed 17 metabolites, including caffeic acid, and berberine, a remarkable alkaloid from the genus Berberis L. The metabolic pattern changes of the leaves in the course of time were found to be seasonally dependent, probably due to the variability of seasonal and environmental trends. This metabolites overview is of great importance in understanding plant (bio)chemistry and mediating plant survival and is influenceable by interacting environmental means. Moreover, the study will be helpful in medicinal purposes, health sciences, crop evaluations, and genetic and biotechnological research.

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Enterococcus faecalis infections represent a health concern, mainly in oral diseases, in which treatments with chlorhexidine solution (0.2%) are often used; however, it presents high toxicity degree and several side effects. Based on this, the use of natural products as an alternative to treatment has been explored. Nonetheless, plant extracts have poor organoleptic characteristics that impair theirs in natura use. Therefore, this work aimed to evaluate the analytical profile, biological activity, and cytotoxicity in vitro of S. brasiliensis-loaded chitosan microparticles (CMSb) produced using different aspersion flow rates. The analytical fingerprint was obtained by FTIR and NIR spectra. Principal components analysis (PCA) was used to verify the similarity between the samples. The crystallinity degree was evaluated by X-ray diffraction (XRD). Phytochemical screening (PS) was performed to quantify phytocompounds. Antimicrobial activity was evaluated by minimum inhibitory concentration (MIC). Antibiofilm activity and bactericidal kinetics against E. faecalis (ATCC 29212 and MB 146-clinical isolated) were also assessed. The hemolytic potential was performed to evaluate the cytotoxicity. Data provided by FTIR, NIR, and PCA analyses revealed chemical similarity between all CMSb. Furthermore, the results from XRD analysis showed that the obtained CMSb present amorphous characteristic. Tannins and polyphenols were accurately quantified by the PS, but methodology limitations did not allow the flavonoid quantification. The low hemolytic potential assay indicates that all samples are safe. Antimicrobial assays revealed that CMSb were able to inhibit not only the E. faecalis ATCC growth but also the biofilm formation. Only one CMSb sample was able to inhibit the clinical strain. These results highlighted the CMSb antimicrobial potential and revealed this system as a promising product to treat infections caused by E. faecalis.

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BACKGROUND: In Brazil, over the last few years there has been an increase in the production and consumption of goat cheeses. In addition, there was also a demand to create options to use the whey extracted during the production of cheeses. Whey can be used as an ingredient in the development of many products. Therefore, knowing its composition is a matter of utmost importance, considering that the reference methods of food analysis require time, trained labor and expensive reagents for its execution. METHODS: Goat whey samples produced in winter and summer were submitted to proximate composition analysis (moisture, total solids, ashes, proteins, fat and carbohydrates by difference) using reference methods and near infrared spectroscopy (NIRS). The spectral data was preprocessed by baseline correction and the Savitzky-Golay derivative. The models were built using Partial Least Square Regression (PLSR) with raw and preprocessed data for each dependent variable (proximate composition parameter). RESULTS: The average whey composition values obtained using the referenced methods were in accordance with the consulted literature. The composition did not differ significantly (p > 0.05) between the summer and winter whey samples. The PLSR models were made available using the following figures of merit: coefficients of determination of the calibration and prediction models (R 2cal and R 2pred, respectively) and the Root Mean Squared Error Calibration and Prediction (RMSEC and RMSEP, respectively). The best models used raw data for fat and protein determinations and the values obtained by NIRS for both parameters were consistent with their referenced methods. Consequently, NIRS can be used to determine fat and protein in goat whey.

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Studies of the phytotoxic effects between plants can be a crucial tool in the discovery of innovative compounds with herbicide potential. In this sense, we can highlight ruzigrass (Urochloa ruziziensis), which is traditionally used in the crop rotation system in order to reduce weed emergence. The aim of this work was to characterize the secondary metabolites of ruzigrass and to evaluate its phytotoxic effects. In total, eight compounds were isolated: friedelin, oleanolic acid, α-amyrin, 1-dehydrodiosgenone, sitosterol and stigmasterol glycosides, tricin and p-coumaric acid. Phytotoxic effects of the crude methanolic extract and fractions of ruzigrass were assessed using germination rate, initial seedling growth, and biomass of Bidens pilosa, Euphorbia heterophylla and Ipomoea grandifolia. Chemometric analysis discriminated the weed species into three groups, and B. pilosa was the most affected by fractions of ruzigrass. The phytotoxic activities of 1-dehydrodiosgenone, tricin, and p-coumaric acid are also reported, and p-coumaric acid and 1-dehydrodiosgenone were active against B. pilosa.

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This work was focused on evaluating the effects of polycarboxylic acid addition and retrogradation phenomenon on tribological performance, thermal, and mechanical properties of both, bioadhesives and sustainable panels. The rheological behavior of adhesives was affected by retrogradation, exhibiting formulations containing CA higher elastic modulus than those with BTCA, regardless of the acid concentration. With regard to tribomechanical properties, panels formulated with CA20 and BTCA80 adhesives presented the lower friction coefficient and wear degree. Thermocompression process induced a crosslinking reaction between wood fibers and starch-based adhesives, leading to more hydrophobic and thermally stable matrices in the presence of BTCA. The selection of the adhesive formulation depends on the moment of its use, since retrogradation limits its performance and that of the derived sustainable panels, being the adhesive CA20 more appropriate in freshly prepared formulations. Meanwhile, when the storage of the adhesive prepared in batch is required, the BTCA80 formulation would be more suitable. Thus, bioinspired materials can provide a valuable insight towards incorporating starch-based adhesives for wood applications.

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Cardiovascular diseases (CVDs) present high prevalence rates in the current world. It is estimated that approximately one-third of the global deaths are related to CVDs, and thus there is still a need for novel drugs to treat these disorders. We serendipitously discovered that LINS01005 (5a) is a potent vasodilating agent in rat aorta, and therefore a set of analogues were evaluated for the vasodilating potency in Wistar and SHR rat thoracic aorta precontracted with norepinephrine, with endothelium intact (E+) or denuded (E-) aortic rings. Compounds 5a and 5b were the most potent, showing submicromolar potency for endothelium intact vessels (EC50 853 and 941 nM, respectively) and micromolar values for E- vessels (EC50 2.4 and 7.1 µM, respectively). These compounds were indeed significantly more potent vasodilating agents in SHR-derived aortic rings (p < 0.001), showing nanomolar potency for 5a [EC50 2.4 nM (E+) 9.0 nM (E-)] and 5b [EC50 20 nM (E+) 2.1 µM (E-)]. SAR analysis though PCA and HCA were performed, suggesting that N-phenylpiperazine is essential to the activity, while increasing volume in the substituted aromatic moiety is detrimental to the potency. This is the first report of the vasodilating properties of such compounds, and studies regarding the mechanism of action are in progress in our group.

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Requirements for blends of drop-in petroleum/bio-derived fuels with specific thermophysical and thermochemical properties highlights the need for chemometric models that can predict these properties. Multivariate calibration methods were evaluated using the measured thermograms (i.e., change in temperature with time) of 11 diesel/biodiesel fuel blends (including four repeated runs for each fuel blend). Two National Institute of Standards and Technology Standard Reference Material® (SRM®) pure fuels were blended by serial dilution to produce fuels having diesel/biodiesel volumetric fractions between (0 to 100) %. The fuels were evaluated for the prepared fuel-blend volume fraction and total specific energy release (heating value), using a laser-driven calorimetry technique, termed 'laser-driven thermal reactor'. The experimental apparatus consists of a copper sphere-shaped reactor (mounted at the center of a stainless-steel chamber) that is heated by a high-power continuous wave Nd:YAG laser. Prior to heating by the laser, liquid sample is injected onto a copper pan substrate that rests near the center of the reactor and is in contact with a fine-wire thermocouple. A second thermocouple is in contact with the sphere-reactor inner surface. The thermograms are then used to evaluate for the thermochemical characteristic of interest. Partial least squares (PLS) and support vector machine (SVM) models were constructed and evaluated for SRM-fuel-blend quantification, and determination of prepared fuel-blend volume fraction and heating value. Quantification of the fuel-blend thermograms by the SVM method was found to better correlate with the experimental results than PLS. The combination of laser-driven calorimetry and multivariate calibration methods has demonstrated the potential application of using thermograms for fuels quantification and analysis of fuel-blend properties.

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The effects of processing on the chemical, physicochemical, enzymatic, and volatile metabolic composition of pitaya pulp were assessed for the first time. To this end, the following treatments to obtain pitaya pulp were evaluated: Treatment A (TA, pulp processing without ascorbic acid), Treatment B (TB, whole fruit processing with ascorbic acid), and Control (whole fruit processing without ascorbic acid). The treatment employed in TB resulted in low polyphenol oxidase and peroxidase activity, and no significant chemical or physicochemical alterations in most parameters evaluated. In addition, TB presents high yields and fiber content compared to the TA or Control. For metabolic analysis, Gas Chromatography-Mass Spectrometry (GC-MS) was effective for the simultaneous determination of 80 volatile metabolites in pitaya. Chemometric analyses was used to efficiently distinguish the volatile compounds of each treatment, and demonstrated that TB presents an interesting volatile profile due the conservation or agregation of compounds.

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