Siolmatra brasiliensis stem extract ameliorates antioxidant defenses and mitigates glycoxidative stress in mice with high-fat diet-induced obesity.

BACKGROUND: Obesity is accompanied by insulin resistance and glucose intolerance, which favor the onset of complications related to oxidative stress. The aim of this study was to investigate the effects and underlying mechanisms of hydroethanolic extract from Siolmatra brasiliensis stems on insulin resistance, glucose intolerance, advanced glycation end product (AGE) formation, and oxidative stress in mice with induced obesity. METHODS: C57BL-6 J mice were fed a high-fat diet for 14 weeks and treated with 125 or 250 mg/kg S. brasiliensis extract during the last 7 weeks. The study assessed glucose tolerance and insulin sensitivity, lipid profile, plasma levels of thiobarbituric acid reactive substances (TBARS, biomarkers of oxidative damage), fluorescent AGEs (biomarkers of advanced glycation), and paraoxonase 1 (PON1) activity (antioxidant enzyme). The activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in the liver and kidneys were also investigated. RESULTS: Siolmatra brasiliensis extract had antiobesogenic effects; improved insulin sensitivity and glucose tolerance; decreased the total plasma cholesterol levels; decreased the levels of glycoxidative stress biomarkers, including AGEs (plasma, liver, kidneys) and TBARS (liver, kidneys); and also improved endogenous antioxidant defenses by increasing the activities of PON1 (plasma), SOD (kidneys), CAT (liver, kidneys), and GSH-Px (kidneys). CONCLUSION: This study expands on our knowledge about the pharmacological properties of S. brasiliensis and substantiates the potential of this plant species to be used as a complementary therapeutic agent to alleviate the metabolic dysfunctions resulting from dyslipidemia and glycoxidative stress.

Acaricidal activity of Acmella oleracea (Asteraceae) extract against Rhipicephalus microplus: What is the influence of spilanthol?

The present study was carried out to evaluate and compare the acaricidal activity of different fractions of Acmella oleracea methanolic extract, containing 0.0 % (F1), 24.5 % (F2), 48.0 % (F3) and 100 % (F4) of spilanthol, on unfed larvae and engorged females from the same Rhipicephalus microplus population. To obtain these fractions, the crude extract was subjected to different extraction procedures using increasingly polarized solvents to isolate the spilanthol compound. The Larval Packet Test was used to evaluate acaricidal activity in unfed larvae at concentrations ranging from 0.2 to 25.0 mg/mL, while for engorged females, the Adult Immersion Test was performed at concentrations from 3.1 to 25.0 mg/mL. The F1 fraction showed no activity on unfed larvae, while a control percentage of 44.6 % was observed at a concentration of 25.0 mg/mL for engorged females. For unfed larvae, the F2 fraction resulted in 95.7 % mortality at a concentration of 1.6 mg/mL, with a control percentage of 92.7 % for engorged females at a concentration of 12.5 mg/mL. Fractions F3 and F4 had similar activity against unfed larvae, with mortality >84.0 % from the concentration of 0.8 mg/mL. This similarity between the fractions was also observed for engorged females from a concentration of 12.5 mg/mL, resulting a control percentage >94.0 %. These results demonstrate that the presence of spilanthol is an important factor for the acaricidal activity of A. oleracea extract. Fraction extracts with 24.5, 48 and 100 % of spilanthol have similar acaricidal activity on R. microplus.

Study on the Antinociceptive Activity and Mechanism of Action of Isolated Saponins from Siolmatra brasiliensis (Cogn.) Baill.

Infusions of roots of Siolmatra brasiliensis (Cogn.) Baill, ("taiuiá", "cipó-tauá") are used for toothache pain and ulcers. We aimed to study the antinociceptive effects and identify the possible mechanism of action of this plant and its isolated substances (cayaponoside A1, cayaponoside B4, cayaponoside D, and siolmatroside I). Hydroethanol extract (HE), ethyl acetate fraction (EtOAc), and isolated saponins were evaluated in chemical and thermal models of pain in mice. Animals were orally pretreated and evaluated in the capsaicin- or glutamate-induced licking and in the hot plate tests. The antinociceptive mechanism of action was evaluated using the hot plate test with the following pretreatments: Atropine (cholinergic antagonist), naloxone (opioid antagonist), or L-NAME (nitric oxide synthase inhibitor). All extracts and isolated saponins increased the area under the curve in the hot plate test. Tested substances induced a higher effect than the morphine-treated group. Our data suggest that stems of S. brasiliensis and their isolated substances present antinociceptive effects. Cholinergic and opioidergic pathways seem to be involved in their mechanism of action. Taken together our data corroborate the traditional use of the plant and expands the information regarding its use.

Characterization of a Urochloa humidicola methanol extract as a phytogenic additive for ruminants / Caracterização do extrato metanólico de Urochloa humidicola como aditivo fitogênico para ruminantes

This survey aimed to characterize a Urochloa humidicola methanol extract regarding the presence of secondary metabolites classes and to determine its bromatological composition. U. humidicola samples were dried under shade, milled on a 2-mm sieve by a Willey mill. The solution obtained was filtered using filter paper and concentrated in a rotary evaporator under reduced pressure; the concentrated residue was then placed in an open vessel to complete solvent removal using continuous air flow dryers. Phytochemical prospection tests and bromatological composition analyses were performed on the dry methanol extract, and the results were compared to in natura U. humidicola. The methanol extract had 10.2% CP and 35% EE and in natura U. humidicola had 5.17% CP and 1.57% EE, with a difference (P < 0.05) of 5% by Fisher's test. In natura U. humidicola had 75.59% NDF, 40.77% ADF, 38.82% HEM, 29.93% CEL, and 7.19% LIG. Methanol extraction by cold maceration reduced the LIG (0.17%) and CEL (0.21%) contents as only soluble constituents were extracted. A phytochemical assay was positive for the presence of saponins, tannins, alkaloids, non-protein amino acids, carbohydrates, cardiac glycosides, steroids, tripernoids, catechins, and saccharides and was negative for the presence of flavonoids and purines. The U. humidicola methanol extract possesses traits that allow its use as a phytogenic and natural additive.

Objetivou-se neste estudo caracterizar o extrato metanólico de Urochloa humidicola, quanto à presença de classes de metabólitos secundários presentes bem como determinar a sua composição bromatológica. Para isto, amostras da parte aérea de U. humidicola foram secas à sombra, moídas em moinho tipo Willey em partículas de 2 mm, submetidas à extração por maceração a frio com metanol, a solução obtida foi concentrada em rotaevaporador e posto para termina a secagem sob fluxo de ar contínuo. O extrato metanólico seco foi submetido aos testes de prospecção fitoquímica e análises de composição bromatológica comparado com a U. humidicola in natura. O extrato apresentou 10,2% de PB e 35% de EE e U. humidicola in natura apresentou 5,17 % de PB e 1,57% de EE, diferindo entre si (P<0,05) pelo teste de Fisher a 5% de significância. A U. humidicola in natura apresentou teores de FDN (75,59%), FDA (40,77%), hemicelulose (38,82%), celulose (29,93%) e lignina (7,19%). O método de extração por maceração a frio com metanol contribuiu para a diminuição dos teores de lignina (0,17%) e celulose (0,21%), por extrair somente os constituintes solúveis. O ensaio fitoquímico apresentou presença positiva para saponina, tanino, alcaloides, aminoácidos não proteicos, carboidratos, glicosídeos cardioativos, esteroides e tripernoides, catequinas e sacarídeos, e negativa para a presença de flavonoides e purinas. O extrato metanólico de Urochloa humidicola apresenta características que permitem seu uso como aditivo natural ou fitogênico.

Length-scale Specific Crystalline Structural Changes Induced by Molecular Randomization of Pequi Oil.

Pequi fruit (Caryocar brasiliense Camb) is considered important since its pulp has a high content of oil and carotenoids. The oil's triacylglycerols (TAGs) contain mainly oleic (~57%) and palmitic (~36%) fatty acids, distributed primarily among POO, POP/PPO, and OOO TAGs. It displays a tendency to fractionate upon storage and has a relatively low melting temperature (SFC of 4% at 25°C). Pequi oil was modified through chemical interesterification, which increased the PPP content to ~6%. This caused a flattening in the SFC-temperature profile, raising the end of melt temperature significantly (SFC of 4% at 39°C). The interesterified oil does not fractionate and is thermally stable up to 40°C, with an SFC-temperature profile resembling that of roll-in shortening (SFC of 31% at 16°C) despite containing high amounts of oleic acid. Crystallization and melting behavior changed. Crystal packing became more disorganized as evidenced by a significant decrease in crystalline domain size in the [001] direction from 42.3 nm to 32.1 nm. Polymorphism remained of the triclinic (ß) subcell type but polytypism changed from the 3L to the 2L type. Polarized light microscopy demonstrated that interesterification dramatically decreased crystal size, consistent with a higher rate of nucleation in the material. Moreover, the dramatic improvement in physical stability and functionality was not accompanied by a significant decrease in total carotenoid content (~390 mg/kg).

A new dammarane saponin and other triterpenoids from Siolmatra brasiliensis and evaluation of the antidiabetic activity of its extract.

Context Siolmatra brasiliensis (Cogn.) Baill (Cucurbitaceae) is a climbing plant widely used for the treatment of diabetes mellitus symptoms. Objective This work evaluates the antidiabetic activity of an extract of S. brasiliensis in streptozotocin-diabetic rats and promotes the phytochemical investigation to isolate the major compounds of the same extract. Materials and methods Male Wistar rats were divided into normal (N) and diabetic rats (DC) treated with water; diabetic rats treated with 3U insulin (DI) or with 250 (DSb250) or 500 mg/kg (DSb500) of hydroalcoholic extract of the stalks of S. brasiliensis, via oral gavage, for 21 days. Physiological and biochemical parameters classically altered in diabetes were monitored. The triterpenoids were isolated from the ethyl acetate fraction under silica gel column chromatography and Sephadex-LH20 methods and their structures were determined by NMR, HR-ESI-MS and DC analysis. Results When compared with DC, DSb250 rats showed a reduction in the hyperglycemia (DC: 26.46 ± 0.69 versus DSb250: 19.67 ± 1.06 mmol/L) and glycosuria (DC: 43.02 ± 3.19 versus DSb250: 28.46 ± 2.14 mmol/24 h) and increase in hepatic glycogen (DC: 14.44 ± 1.26 versus DSb250: 22.08 ± 4.26 mg/g). Three known cucurbitacins were isolated from a hydroalcoholic extract of S. brasiliensis, i.e., cayaponosides A1, B4, D, and a new dammarane saponin 3-O-ß-d-gentiobiosyl-26-O-ß-d-glucopyranosyl-20-hydroxydammar-24-ene. The structures of these compounds were elucidated by spectral data analysis of the natural products and their acetyl derivatives. Discussion and conclusion The known cucurbitacins and/or the new identified saponin may be related with the antidiabetic activity of S. brasiliensis.

Acaricidal activity of essential oil from Lippia sidoides on unengorged larvae and nymphs of Rhipicephalus sanguineus (Acari: Ixodidae) and Amblyomma cajennense (Acari: Ixodidae).

The aims of this work were to identify the compounds and to investigate the acaricidal activity of the essential oil of Lippia sidoides for unengorged larvae and nymphs of Rhipicephalus sanguineus and Amblyomma cajennense. The oil was analyzed by gas chromatography and gas chromatography/mass spectrometry. In total, 22 compounds comprising 98.5% of the total peak area were identified. The major constituent of the essential oil was thymol (69.9%). The acaricidal activity against larvae and nymphs was assessed using a modified larval packet test. In all experiments, oils were tested at concentrations of 2.35, 4.70, 9.40 14.10 and 18.80 mg/mL. The mortalities of larvae and nymphs of R. sanguineus were 20.6, 47.8, 73.6, 99.5 and 99.0% and 12.0, 50.0, 76.3, 96.0 and 96.1%, respectively. For larvae and nymphs of A. cajennense the rates of mortality were 41.9, 63.3, 77.8, 82.5 and 100.0% and 0.0, 32.8, 64.8, 71.1 and 94.0%, respectively. The LC 90 values of the L. sidoides oil were 11.56 and 12.97 mg/mL for larvae and nymphs of R. sanguineus and 15.70 and 18.52 mg/mL for larvae and nymphs of A. cajennense, respectively. The essential oil from L. sidoides has acaricidal activity on unengorged larvae and nymphs of R. sanguineus and A. cajennense.