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.

Cosmetic application of the stem-bark extract of Bertholletia excelsa H.B.K.

OBJECTIVE: The Amazon has a rich biodiversity where many different plant species can be found. This diversity is an important source of bioactive substances, mainly due to the different structural components of their phytometabolites. Research for natural products is a strategy for the development of new agents in therapeutic applications, especially cosmetic applications, that have better pharmacological potential. Within this perspective, the objective of the study was to investigate the cosmetic application (anti-aging potential) of the stem-bark extract of Bertholletia excelsa H.B.K - (SBEBE), popularly known as the Brazil nut tree, here called SBEBE, a noble plant species of the Amazon that is rich in selenium. METHODS: Enzymatic, glycation, proliferation, cell-healing, collagen quantification, toxicity and genotoxicity assays were used. RESULTS: Among the enzymes involved in the extracellular matrix of the skin, SBEBE was able to inhibit only elastase (62.67 ± 3.75) when compared to the standard sivelestat (89.04 ± 0.53), and the extract was also able to inhibit both the oxidative and the non-oxidative pathway. When cell toxicity in fibroblasts (MRC-5) and keratinocytes (HACAT) was evaluated, SBEBE did not present toxicity in 24 h of incubation. After this period, the extract showed average cytotoxicity in 48 and 72 h, but not enough to reach the concentration of 50% of MRC-5 fibroblasts. In the trypan blue assay, the extract promoted fibroblast proliferation in 24, 48 and 72 h of incubation, which was evaluated through exponential cell growth, with emphasis mainly on the lowest concentration with results higher than the standard. When the cell healing capacity was evaluated, in 48 h of exposure to fibroblast, SBEBE was able to induce a cell carpet (cell film) in the cell monolayer scratch assay. CONCLUSIONS: SBEBE stimulated collagen production at all concentrations tested. In the alkaline comet assay, at the lowest concentration, the extract did not induce DNA damage when compared to the reference drug doxorubicin. This study proved that SBEBE extract can be considered an ally in the treatment of skin anti-ageing as a possible biotechnological, phytocosmetic product.

OBJECTIF: L'Amazonie possède une riche biodiversité ou l'on trouve de nombreuses espèces végétales différentes. Cette diversité constitue une source importante de substances bioactives, principalement en raison des différents composants structurels de leurs phytométabolites. La recherche de produits naturels est une stratégie de développement de nouveaux agents à applications thérapeutiques, notamment cosmétiques, présentant un meilleur potentiel pharmacologique. Dans cette perspective, l'objectif de l'étude était d'étudier l'application cosmétique (potentiel anti­âge) de l'extrait d'écorce de tige de Bertholletia excelsa H.B.K ­ (SBEBE), communément connu sous le nom de noix du Brésil, ici appelé SBEBE, un arbre noble, espèce végétale d'Amazonie riche en sélénium. MÉTHODES: Des tests enzymatiques, de glycation, de prolifération, de guérison cellulaire, de quantification du collagène, de toxicité et de génotoxicité ont été utilisés. RÉSULTATS: Parmi les enzymes impliquées dans la matrice extracellulaire de la peau, le SBEBE était capable d'inhiber uniquement l'élastase (62,67 +­ 3,75) par rapport au sivelestat standard (89,04 +­ 0,53), et l'extrait était également capable d'inhiber à la fois la voie oxydative et non­oxydative. Lorsque la toxicité cellulaire dans les fibroblastes (MRC­5) et les kératinocytes (HACAT) a été évaluée, SBEBE n'a présenté aucune toxicité en 24 heures d'incubation. Après cette période, l'extrait a montré une cytotoxicité moyenne en 48 et 72 h, mais pas suffisamment pour atteindre la concentration de 50 % de fibroblastes MRC­5. Dans le test au bleu trypan, l'extrait a favorisé la prolifération des fibroblastes en 24, 48 et 72 heures d'incubation, qui a été évaluée par une croissance cellulaire exponentielle, en mettant l'accent principalement sur la concentration la plus faible avec des résultats supérieurs à la norme. Lorsque la capacité de guérison cellulaire a été évaluée, en 48 heures d'exposition aux fibroblastes, SBEBE a pu induire un tapis cellulaire (film cellulaire) dans le test de grattage de la monocouche cellulaire. CONCLUSIONS: SBEBE a stimulé la production de collagène à toutes les concentrations testées. Dans le test alcalin des comètes, à la concentration la plus faible, l'extrait n'a pas induit de dommages à l'ADN par rapport au médicament de référence, la doxorubicine. Cette étude a prouvé que l'extrait de SBEBE peut être considéré comme un allié dans le traitement anti­âge cutané en tant que possible produit biotechnologique et phytocosmétique.

Catalase and Uric Acid Prevent Morphological Damage to the Sperm Flagella of Colossoma macropomum During 96 Hours at Low Storage Temperatures.

Oxidative stress is one of the main causes of loss of sperm function during chilled storage. The aim of the current study was to evaluate the effects of a fructose-based extender, which was supplemented with catalase or uric acid, on the motility, viability, morphological integrity, and lipid peroxidation (LPO) of Colossoma macropomum spermatozoa. Sperm was diluted in extenders containing catalase (0; 0.1; 0.8; and 1.5 kU/L) or uric acid (0; 0.25; 0.5; and 1.0 mmol/L) and then stored at 4.3 ± 0.6°C for 96 hours. The chilling storage time had more significant and pronounced effects on practically all the measured sperm quality parameters than the different concentrations of both antioxidants added to the extenders. This was true for sperm motility, motility duration, sperm viability, and the percentage of normal spermatozoa. In fact, for all these parameters, values were higher in the extenders supplemented with catalase or uric acid, than those not supplemented with these antioxidants, especially after 96 hours. The LPO process showed an antioxidant-dependent response. In catalase-supplemented extenders thiobarbituric acid reactive substance (TBARS) levels increased gradually and significantly with time, but remained stable during the 96 hours of chilled storage in all samples in which uric acid was added. Despite this, TBARS levels were lower in the extenders supplemented with both catalase and uric acid than in those not having these antioxidants. Inverse correlations were found between sperm motility and the damage in sperm flagella. Our findings suggest that the supplementation of an extender with catalase or uric acid is beneficial and protects fish sperm membranes from damage caused by oxidative stress during low-temperature storage. The extenders containing 0.1 kU/L of catalase and 0.25 mmol/L of uric acid provided effective antioxidant protection for the spermatozoa of this important Amazonian fish.

Hypoglycemic effect of the dry leaf extract of Myrcia multiflora in streptozotocin-induced diabetic mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Myrcia multiflora (Lam) DC. is a medicinal plant used in folk medicine for diabetes control, mainly in the Brazilian Amazon. The leaves of this species has already demonstrated antidiabetic properties; however, in mice with type 2 diabetes (DM2), the cumulative effect of the consumption of the dry extract of M. multiflora leaves (Mm) has not yet been reported. AIM OF THE STUDY: To investigate the effect of the dry extract obtained from the infusion of the dried leaves of M. multiflora on the blood glucose levels of diabetic mice. MATERIALS AND METHODS: DM2 was induced in Swiss male mice by a single intraperitoneal injection of streptozotocin [150 mg/kg body weight (bw)]. The animals were divided into two control groups (healthy and diabetic without treatment) and three sample groups that received Mm (25 and 50 mg/kg bw) and acarbose (200 mg/kg bw) by gavage once daily for 28 days (D28). Additionally, biochemical parameters, thiobarbituric acid reactive species (TBARS) levels in the liver, and histopathological analyses of the kidneys and liver were performed. RESULTS: On the seventh day of treatment, a 74.7% reduction in glucose levels were observed in the group of diabetic animals treated with Mm (50 mg/kg bw) when compared to the beginning of the treatment. At D28, the hypoglycemic effect was maintained. The results of the biochemical and histopathological parameters and the TBARS levels suggest that this dry extract exerts nephro- and hepatoprotective effects. CONCLUSIONS: The findings demonstrate the potential that this extract has to inhibit the α-glucosidase enzyme, and it acts similarly to the positive control acarbose. Furthermore, this extract is nephro- and hepatoprotective. Therefore, this dry extract has the potential to be an adjuvant for DM2, which corroborates its use in folk medicine.

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.

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.

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.

Anti-inflammatory and antioxidant properties of Bertholletia excelsa (H. B. K) bark extract / Propiedades antiinflamatorias y antioxidantes del extracto de corteza de Bertholletia excelsa (H. B. K)

Bertholletia excelsa is native to the Amazon Rainforest and is popularly known as the Brazil nut. It has socioeconomic importance due its nuts being a great export product. There are few studies in the literature regarding the biotechnological potential of its bark, although it is used in folk medicine. The aim of this study was to determine the chemical constituents, anti-inflammatory and antioxidant properties of B. excelsa bark extract (BEB). Twelve substances were identified by LC/MS/MS, and cytotoxicity tests were carried out, as well as analyses of nitric oxide production and elimination of free radicals. BEB caused cytoprotection against oxidative stress in macrophages, increased HMOX-1 expression, overcame the antioxidant effects of GPx-1 and reduced its expression and was able to inhibit leukocyte migration in use peritonitis. BEB efficiently attenuated oxidative stress due to its antioxidant and anti-inflammatory properties and, as such, can be used as a safe and effective source of a natural herbal medicine.

Bertholletia excelsa es originaria de la selva amazónica y se la conoce popularmente como nuez de Brasil. Tiene importancia socioeconómica debido a que sus frutos secos son un gran producto de exportación. Existen pocos estudios en la literatura sobre el potencial biotecnológico de su corteza, aunque se utiliza en medicina popular. El objetivo de este estudio fue determinar los componentes químicos, las propiedades antiinflamatorias y antioxidantes del extracto de corteza de B. excelsa (BEB). Se identificaron 12 sustancias mediante LC/MS/MS y se realizaron pruebas de citotoxicidad, así como análisis de producción de óxido nítrico y eliminación de radicales libres. BEB causó citoprotección contra el estrés oxidativo en macrófagos, aumentó la expresión de HMOX-1, superó los efectos antioxidantes de GPx-1 y redujo su expresión y fue capaz de inhibir la migración de leucocitos en la peritonitis de uso. BEB atenuó eficazmente el estrés oxidativo debido a sus propiedades antioxidantes y antiinflamatorias y, como tal, puede utilizarse como una fuente segura y eficaz de un medicamento a base de hierbas naturales.

Guaianolide sesquiterpene lactones and aporphine alkaloids from the stem bark of Guatteria friesiana.

Three guaianolide sesquiterpenes, denoted guatterfriesols A-C, and four aporphine alkaloid derivatives were isolated from the stem bark of the Amazonian plant Guatteria friesiana. Thus far, sesquiterpene lactones have not been described in Annonaceae. Structures of the previously undescribed compounds were established by using 1D and 2D NMR spectroscopy in combination with MS. The absolute stereochemistry was assigned via NOE NMR experiments, ECD spectroscopy, and theoretical calculations using the TDDFT approach. Among the isolated compounds, the alkaloid guatterfriesidine showed anti-glycation activity by inhibiting the formation of advanced glycation end-products (AGEs) through the prevention of oxidation in both BSA/methylglyoxal and BSA/fructose systems.

Remela de cachorro (Clavija lancifolia Desf.) fruits from South Amazon: Phenolic composition, biological potential, and aroma analysis.

Remela de cachorro (Clavija lancifolia Desf.) is an Amazonian native fruit consumed specially in the Purus microregion. Because of its rarity, restricted consumption, and the lack of knowledge about its chemical composition, remela de cachorro fruit was studied in relation to its phenolic and aroma constitution. Using liquid chromatography tandem mass spectrometry (LC-MS/MS), 11 compounds (flavonoids and its glucosides along with organic acids) were tentatively identified by fragmentation patterns. A previously validated method was applied to quantify common antioxidant compounds in the raw pulps, for which kaempferol was the main compound. Gas chromatography mass spectrometry (GC-MS) with headspace solid-phase microextraction (HS-SPME) was employed to assess the aroma composition of remela de cachorro fruit. A total of 27 volatile organic compounds (VOCs) were identified for this fruit, for which benzaldehyde and linalool were the main VOCs. Furthermore, biological activities, such as antioxidant capacity (ABTS, DPPH, and ORAC methods), cytotoxicity, and α-glucosidase and lipase inhibitions of the hydroalcoholic extract of remela de cachorro fruit were evaluated. In vitro biological assays revealed the potential of this fruit as a bioactive food that should be further studied and explored in Amazonian products.