NMR and multivariate methods: Identification of chemical markers in extracts of pedra-ume-caá and their antiglycation, antioxidant, and enzymatic inhibition activities.

INTRODUCTION: In Brazil, the plant group popularly known as "pedra-ume-caá" is used in folk medicine for the treatment of diabetes, and its raw material is commonly sold. OBJECTIVE: The aim of the study was to apply a method for chemical identification of extracts of dry pedra-ume-caá leaves using HPLC-high-resolution mass spectrometry (HRMS) and NMR and develop a multivariate model with NMR data to authenticate commercial samples. In addition, to evaluate the biological activities of the extracts. MATERIALS AND METHODS: Dry extracts of Myrcia multiflora, Myrcia amazonica, Myrcia guianensis, Myrcia sylvatica, Eugenia punicifolia leaves, and 15 commercial samples (sold in Manaus and Belém, Brazil) were prepared by infusion. All the extracts were analysed using HPLC-high-resolution mass spectrometry (HRMS), NMR, principal component analysis (PCA), and hierarchical cluster analysis (HCA). The antidiabetic effect of extracts was evaluated according to enzymatic inhibition. Their content of total phenols, cell viability, and antioxidant and antiglycation activities were also determined. RESULTS: HPLC-HRMS and NMR analysis of these extracts permitted the identification of 17 compounds. 1H NMR data combined with multivariate analyses allowed us to conclude that catechin, myricitrin, quercitrin, and gallic and quinic acids are the main chemical markers of pedra-ume-caá species. These markers were identified in 15 commercial samples of pedra-ume-caá. Additionally, only the extracts of M. multiflora and E. punicifolia inhibited α-glucosidase. All the extracts inhibited the formation of advanced glycation end products (AGEs) and showed free-radical-scavenging activity. These extracts did not present cytotoxicity. CONCLUSION: This study revealed the chemical markers of matrices, and it was possible to differentiate the materials marketed as pedra-ume-caá. Moreover, this study corroborates the potential of these species for treating diabetes.

Hypoglycemic effect and toxicity of the dry extract of Eugenia biflora (L.) DC. leaves.

ETHNOPHARMACOLOGICAL RELEVANCE: The leaves of Eugenia biflora (Myrtaceae) are traditionally used by Amazonian populations for the control of diabetes. However, their chemical composition has not yet been described and pharmacological evidence has not been reported. OBJECTIVE: This study aimed to identify the chemical constituents and evaluate the hypoglycemic and toxic effect of the dry extract of the E. biflora leaves (DEEB). MATERIALS AND METHODS: DEEB, obtained by infusion, was analyzed using LC-HRMS and NMR, whose the catechin flavonoid was quantified using NMR. The antidiabetic effect of DEEB was evaluated according to its inhibition of the enzymes α-amylase and α-glucosidase, as well as the content of total phenols, free radical scavengingand antiglycation activities, and its in vitro cell viability. Oral maltose tolerance and chronic multiple dose tests (28 days) in streptozotocin-induced diabetic mice (STZ) were performed. The hypoglycemic effect and toxicity of this extract were evaluated in the multiple dose assay. Biochemical parameters, hemolysis, and levels of the thiobarbituric acid reactive species in the liver were investigated and histopathological analyses of the kidneys and liver were performed. RESULTS: Eight phenolic compounds were identified, with catechin (15.5 ± 1.7 mg g-1) being the majority compound and a possible chemical marker of DEEB. The extract showed inhibition activity of the enzyme α-glucosidase. Chronic administration of DEEB (50 mg/kg of body weight) reduced glucose levels in diabetic animals, similar to acarbose; however, DEEB (100 and 200 mg/kg bw) caused premature death of mice by D22 of the treatment. Our data indicate that one of the mechanisms of toxicity in DEEB may be related to the aggravation of oxidative stress in the liver. This histopathological study indicated that DEEB failed to minimize the progression of the toxicity of diabetes caused by STZ. CONCLUSIONS: This study demonstrated the hypoglycemic potential of E. biflora leaves. However, the prolonged use of this tea can be harmful to its users due to its considerable toxicity, which needs to be better investigated.

Physicochemical Characterization, Stability and Cytotoxicity of a Blue Dye Obtained from Genipap Fruit (Genipa americana L.).

RESEARCH BACKGROUND: The current commercial scenario indicates an increase in the demand for natural dyes. Compared to synthetic dyes, natural ones have the advantage of being sustainable, making them of great interest for the food and cosmetic industries. The development of new natural dyes is necessary, as well as the carrying out of complementary research regarding the existing ones. EXPERIMENTAL APPROACH: The present study aims to characterize the physicochemical and biological characteristics of the dye obtained from dehydrated endocarp of the genipap (Genipa americana) fruit, as well as perform the relevant stability and cytotoxicity tests. The chemical characterization was performed by HPLC-MS/MS analyses. The stability studies were carried out by spectrophotometry and cytotoxicity assays using cell culture and fluorometric methods. RESULTS AND CONCLUSIONS: After dehydration and milling of the fruit endocarp, water was added to the obtained powder (in the ratio 4:1) to extract the dye. Five compounds were elucidated using HPLC-MS/MS and confirmed the presence of the geniposide as its main compound. With the X-ray diffraction and electron microscopy analysis, we characterised the obtained powder as being amorphous and of porous structure with a variable size. The thermogravimetric analysis indicated a maximum loss of 61% mass after exposure to a temperature range from 240 to 760 °C. The obtained blue dye was stable in the absence of light, at room temperature and had neutral pH. In the cytotoxicity assay, (95.0±1.3) % of viable human fibroblasts were observed after exposure to this dye. The genipap fruit can be a viable alternative to produce a natural blue dye, since it is easy to obtain and has very low toxicity in food, pharmaceutical or cosmetic products. NOVELTY AND SCIENTIFIC CONTRIBUTION: This study demonstrates for the first time the physicochemical and biological properties of a natural blue dye from G. americana fruit.

qNMR quantification of phenolic compounds in dry extract of Myrcia multiflora leaves and its antioxidant, anti-AGE, and enzymatic inhibition activities.

Myrcia multiflora (Lam.) DC. is often used in Brazilian folk medicine to control diabetes. Analysis using HPLC-HRMS and NMR of the dry extract from the infusion of leaves of this species revealed twelve phenolic compounds. Among these compounds, chlorogenic acid (1), 4-O-caffeoylquinic acid (2), corilagin (3), chebulagic acid (4), pedunculagin (5), quercetin-3-O-ß-2″-galloylglucoside (7), and kaempferol-3-O-rhamnoside (12) are described for the first time in this matrix. Furthermore, six compounds were quantified using qNMR. The compounds in the dry extracts are 3, 6 (myricetin-3-O-d-glucoside), 8 (myricitrin), 9 (hyperoside), 10 (guaijaverin) and 11 (quercitrin). These compounds may be considered chemical markers in this matrix. In addition, this extract presents activities of α-glucosidase inhibition (IC50 = 79.9 µg mL-1) and glycation in vitro (IC50 = 10.2 µg mL-1), in addition to antioxidant activity against DPPH and ABTS radicals (1,856.7 and 1,032.0 µmol TEq, respectively). This extract did not show significant cytotoxicity in human fibroblasts. Therefore, the enzymatic inhibition, anti-AGE (advanced glycation end-products) and antioxidant activities of Myrcia multiflora leaves corroborated its antidiabetic therapeutic potential and instigates future preclinical studies aimed at the treatment of diabetes mellitus and its complications.

Role of gas chromatography and olfactometry to understand the wine aroma: Achievements denoted by multidimensional analysis.

The human nose has been used as a detector in gas chromatography analysis to evaluate odoriferous compounds related to aroma and quality of wine. Several olfactometric techniques are available to access the description, intensity, and/or duration of the odor of each compound. Olfactometry can be associated with one-dimensional gas chromatography or multidimensional gas chromatography, including heart-cut gas chromatography and comprehensive two-dimensional gas chromatography. Multidimensional gas chromatography may help to resolve coeluted compounds and detect important trace components for the aroma. The identification of odor-active compounds may help to differentiate wines according to terroir, grapes cultivars used in winemaking or types of aging, understand the role of fungal infection of grapes for wine quality, find the best management practices in vineyard and vinification to obtain the greatest quality. In addition, when the instrumental techniques are combined with sensory analysis, even more accurate information may be obtained regarding the overall wine aroma. This review discloses the state of the art of olfactometric methods and the analytical techniques used to investigate odor-active compounds such as one-dimensional gas chromatography, multidimensional gas chromatography, and comprehensive two-dimensional gas chromatography. The advances in knowledge of wine aroma achieved with the use of these techniques in the target and profiling approaches were also discussed.

Volatile profile and aroma potential of tropical Syrah wines elaborated in different maturation and maceration times using comprehensive two-dimensional gas chromatography and olfactometry.

The influence of different combinations of Syrah grape maturation degree (19, 21 and 23 °Brix) and maceration times (10, 20 and 30 days) on the volatile profile and aroma potential was evaluated for the first time through different chromatographic platforms (GC × GC/TOFMS, GC-O-OSME, GC-FID and GC/MS). GC × GC/TOFMS analyses resulted in 145 identified compounds and among these 29 were determined to be the most important for wine differentiation. The aroma compounds allowed the discrimination of Syrah wines made with grapes macerated for a shorter time (ten days) due to the higher levels of volatile compounds. The evaluation of these wines through GC-O-OSME together with GC-FID, MS resulted in the designation of 19 °Brix as the most appropriate grape maturation degree to obtain a greater number of volatiles with pleasant odor and higher intensity and persistence. GC × GC/TOFMS allowed five and six co-elutions to be resolved, involving, respectively, ten and twelve important wine compounds.

First fish fauna assessment in the Fernando de Noronha Archipelago with BRUVS: Species catalog with underwater imagery / Primeira avaliação da fauna de peixes no Arquipélago de Fernando de Noronha com BRUVS: Catálogo de espécies com imagens subaquáticas

Abstract: Fish fauna assessments with traditional catch methods are undesired in marine reserves. Underwater visual census on the other hand is biased due to fish-diver interactions, such as shyness or avoidance behavior of large-bodied target species. This study presents the first marine ichthyofauna inventory of the Fernando de Noronha Archipelago, off northeastern Brazil, sampled with non-destructive, independent Baited Remote Underwater Video Systems (BRUVS). High fish species richness, totaling 66 species from 28 families and 10 orders, including five elasmobranch species and other large predatory fish, such as barracudas, groupers and snappers, were recorded from 81 underwater video samples. Additionally, all of the 4,398 individuals sighted were associated to up to four different benthic habitat types. A catalog of underwater fish images and a detailed species list with additional information, such as conservation status, are provided.

Resumo: Inventários de ictiofauna com métodos tradicionais de captura são indesejáveis em reservas marinhas. O censo visual subaquático, porém, sofre o viés das interações peixe-mergulhador, tais como comportamentos de timidez ou fuga exercido pelas grandes espécies-alvo de pressões pesqueiras, incluindo, a caça submarina. Esse estudo representa o primeiro inventário da ictiofauna marinha do Arquipélago de Fernando de Noronha, costa nordeste do Brasil, utilizando sistemas não-destrutivos independentes de vídeos subaquáticos com iscas (BRUVS). Uma elevada riqueza de espécies de peixes, com 66 espécies de 28 famílias e 10 ordens, incluindo cinco espécies de elasmobrânquios e outros grandes peixes predadores como barracudas, garoupas e dentões, foi registrada em 81 amostras de vídeos subaquáticos. Adicionalmente, todos os 4.398 indivíduos avistados foram associados a até quatro diferentes tipos de habitats bentônicos. Um catálogo de imagens subaquáticas dos peixes e uma lista de espécies detalhada com informações adicionais, tais como o status de conservação, são fornecidos.

Pedra-ume caá fruit: An Amazon cherry rich in phenolic compounds with antiglycant and antioxidant properties.

Species of Eugenia have been used as an antidiabetic natural source. Chemical, antioxidant and antiglycant screening of extracts from pedra-ume caá (Eugenia punicifolia) fruits were performed. 1H NMR assisted by non-supervised chemometric methods were employed for the evaluation of the chemical profiles which were distinguished according to the color of fruit maturation stages, as well as for pulp and seed fruit. Furthermore, 1H NMR fingerprint analysis of the crude extract allowed the identification of quercitrin and myricitrin, beside other nine compounds. The extracts of the yellow (YP) and green (GP) pulps presented higher antiglycant and antioxidant activities. Fresh juice from E. punicifolia was encapsulated in microcapsules produced with dextrose equivalent (DE) of 10, 20 or 30 as wall materials for the maintainment of their antioxidant and antiglycant properties. The more efficient retention of the bioactive compounds was found using the DE30. The Encapsulation Efficiency (EE) and the Retention Efficiency (RE) of this system was found around 89.7% and 97.6%, respectively. In addition, NMR spectra revealed the presence of flavonoids O-glycosylated (quercitrin and myricitrin) which might be related to the antiglycant and antioxidant activities. The YP presented larger content of quercitrin (117.6 ±â€¯0.4 mg per each 100 g of fresh fruit). Therefore, pedra-ume caá should be employed as an alternative nutraceutical source, as well as intherapeutic pourposes.

Frog volatile compounds: application of in vivo SPME for the characterization of the odorous secretions from two species of Hypsiboas treefrogs.

A novel in vivo design was used in combination with solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS) to characterize the volatile compounds from the skin secretion of two species of tree frogs. Conventional SPME-GC/MS also was used for the analysis of volatiles present in skin samples and for the analysis of volatiles present in the diet and terraria. In total, 40 and 37 compounds were identified in the secretion of Hypsiboas pulchellus and H. riojanus, respectively, of which, 35 were common to both species. Aliphatic aldehydes, a low molecular weight alkadiene, an aromatic alcohol, and other aromatics, ketones, a methoxy pyrazine, sulfur containing compounds, and hemiterpenes are reported here for the first time in anurans. Most of the aliphatic compounds seem to be biosynthesized by the frogs following different metabolic pathways, whereas aromatics and monoterpenes are most likely sequestered from environmental sources. The characteristic smell of the secretion of H. pulchellus described by herpetologists as skunk-like or herbaceous is explained by a complex blend of different odoriferous components. The possible role of the volatiles found in H. pulchellus and H. riojanus is discussed in the context of previous hypotheses about the biological function of volatile secretions in frogs (e.g., sex pheromones, defense secretions against predators, mosquito repellents).

Natural humic substances effects on the life history traits of Latonopsis australis SARS (1888) (Cladocera--Crustacea).

Cultivation medium is one of the first aspects to be considered in zooplankton laboratory cultivation. The use of artificial media does not concern to reproduce natural conditions to the cultivations, which may be achieved by using natural organic compounds like humic substances (HS). This study aimed to evaluate the effects of a concentrate of dissolved organic carbon (DOC) from the Negro River (NR(1)) and an extraction of humic acids (HA) from humus produced by Eisenia andrei on the life history traits of laboratory-based Latonopsis australis SARS (1888). A cohort life table approach was used to provide information about the effectiveness of NR and HA as supplements for the artificial cultivation of L. australis. Additionally, we seek to observe a maximization of L. australis artificial cultivation fitness by expanding the range of HS concentrations. The first experiment demonstrated that the females of L. australis reared under NR10 (mgDOCL(-1)) may have experienced an acceleration of the population life cycle, as the females have proportionally reproduced more and lived shorter than controls. By contrast, the use of the HA did not improve life history traits considered. The expansion of the concentration range (5, 10, 20 and 50 mgDOCL(-1)) corroborated the patterns observed on the first assay. Results for the fitness estimates combined with shorter lifespans than controls demonstrated trade-offs between reproductive output and female longevity reared under NR conditions, with NR20 been suggested as the best L. australis cultivation medium. This response might be associated with hormone-like effects.