Ocotea nutans (Nees) Mez: structural elucidation of C-hetorosides flavonoids and evaluation of their antioxidant and antibacterial properties from ethyl acetate extract.

The Ocotea genus exhibits a variety of pharmacological, antibacterial and antioxidant effects. The aim of the present study was to evaluate the antioxidant potential and antibacterial properties of the ethyl acetate fraction of Ocotea nutans leaves. Isolation and identification of the phenolic compounds from the fraction was also carried out. The isolated compounds were characterised by one- and two-dimensional nuclear magnetic resonance analysis and identified as vitexin (1) and isovitexin (2). The ethyl acetate fraction of Ocotea nutans leaves demonstrated considerable antioxidant potential. The observed minimum inhibitory concentration of 250 µg.mL-1 was classified as a moderate antibacterial activity against Enterococcus faecalis. Findings from this study demonstrate the utility of this plant as a potential source of antioxidant and antibacterial agents.

Characterization and identification of chemical constituents of Ocotea paranaensis Brotto, Baitello, Cervi, & E.P. Santos and their biological properties.

The growing interest in the discovery of new compounds from medicinal plants justifies the study of phytochemical components of these plants and their biological activities. The genus Ocotea exhibits a variety of pharmacological, antimicrobial and antioxidant effects. The aim of the present study was to evaluate the antioxidant potential and antimicrobial properties of the ethyl acetate fraction of Ocotea paranaensis leaves. Isolation and identification of the phenolic compounds from the fraction was also carried out. The isolated compounds were characterized by one and two-dimensional nuclear magnetic resonance analysis and identified as (-) epicatechin (1), quercetin (2), kaempferol (3) and hyperin (4). The ethyl acetate fraction of Ocotea paranaensis leaves demonstrated considerable antioxidant potential. The observed minimum inhibitory concentration of 500 µg/mL was classified as a moderate antibacterial activity against Staphylococcus aureus. Findings from this study demonstrate the utility of this plant as a potential source of antioxidant and antimicrobial agents.

Evaluation of the nutritional composition and antioxidant activity of Bjerkandera adusta

Abstract Bjerkandera adusta, a globally distributed fungus, is commonly used in the nutritional practices of the East Asian population. In this study, we evaluated the nutritional composition of the lyophilized mycelium of B. adusta as well as the phenolic composition and antioxidant activity of its extracts. The mycelium exhibited moisture (7.97 %), ash (3.27 %), and fiber (5.31 %) content values similar to the established values reported in the available literature. In addition, a high protein (9.32 %) and carbohydrate (63.45 %) content was shown, with a low lipid (1.36 %) content. The energy value per 100 g sample of mycelium was 1445.85 kJ. The results obtained indicated a statistically significant variation (p < 0.05) in the phenolic composition (81.84-110.96 mg gallic acid equivalents (GAE) per g of extract), free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity (IC50 29.05-340.46 µg·mL-1), phosphomolybdenum antioxidant content (34.89-55.64 %), reduction of ferricyanide ion (66.55-69.4 %), and thiobarbituric acid reactive substance (TBARS) values (44.66-133.03 %). These results are unprecedented for this species and emphasize its nutraceutical potential.

A novel approach to Cestrum intermedium (mata-boi): anatomical and physical-chemical characterization, in vitro biological activities, and metabolites of a Brazilian native species

Abstract The Brazilian native species Cestrum intermedium, known as mata-boi, induces hepatotoxicity and death when ingested by cattle. While most studies on this species focus on toxicological features, our study is the first to describe the anatomy and in vitro biological activities of Cestrum intermedium. We investigated adult leaves and stems by histochemistry, described their anatomy, performed physical-chemical analysis, determined in vitro antioxidant and antimicrobial activities, and identified secondary metabolites. A few noteworthy anatomical features were the anomocytic stomata on the abaxial surface and the absence of trichomes, in addition to the circular shaped petiole with two projections on the adaxial surface. Histochemical analysis showed chemical markers such as alkaloids, usually reported as toxic, and terpenoids. Potassium nitrate (ATR-FTIR) and lupeol palmitate (NMR) were detected on the crude stem extract. Thermogravimetric and physical-chemical analysis provided fingerprint parameters for the species. Minimal Inhibitory Concentration (MIC) assay revealed that Staphylococcus aureus, Staphylococcus epidermidis, and Candida albicans were weakly inhibited by extract samples. Chloroform and ethyl acetate fractions presented high phenolic content, which resulted in in vitro antioxidant activity. These novel features expand the knowledge about this species, considering that previous studies mainly focused on its toxicity. Our study also provided characteristics that may help in avoiding misidentification between Cestrum members, especially when taxonomic keys cannot be employed, as in the absence of flowers and fruits.

Inhibition of α-glucosidase, pancreatic lipase, and antioxidant property of Myrcia hatschbachii D. Legrand containing gallic and ellagic acids / Inhibición de la α-glucosidasa, la lipasa pancreática y la propiedad antioxidante de Myrcia hatschbachii D. Legrand que contiene ácidos gálico y elágico

Several species of the Myrcia genus have been used in folk medicine to treat diabetes. Therefore, the aim of this work was to investigate the inhibitory activity of α-glucosidase and pancreatic lipase in the crude extract (EBF) and in the ethyl acetate fraction (FFA) of Myrcia hatschbachii, as well as to identify isolated phenolic compounds and to evaluate the antioxidant property and preliminary in vitro toxicity against Artemia salina. EBF (IC50: 3.21 µg/mL) and FFA (IC50: 1.14 µg/mL) showed inhibitory activity superior to acarbose (IC50: 193.65 µg/mL). In addition, they showed inhibitory effects of pancreatic lipase (IC50: 556.58 µg/mL for EBF and 532.68 µg/mL for FFA), antioxidant potential, absence of preliminary toxicity and presence of gallic andellagic acids in FFA. The relevant results in the inhibition of α-glucosidase and pancreatic lipase motivate new studies for the development of herbal medicines that assist in the treatment of diabetic patients.

Varias especies del género Myrcia se han utilizado en la medicina popular para tratar la diabetes. Por lo tanto, el objetivo de este trabajo fue investigar la actividad inhibitoria de la α-glucosidasa y la lipasa pancreática en el extracto crudo (EBF) y en la fracción de acetato de etilo (FFA) de Myrcia hatschbachii, así como identificar compuestos fenólicos aislados y evaluar la propiedad antioxidante y toxicidad in vitro preliminar contra Artemia salina. EBF (IC50: 3.21 µg/mL) y FFA (IC50: 1.14 µg/mL) mostraron una actividad inhibitoria superior a la acarbosa (IC50: 193.65 µg/mL). Además, mostraron efectos inhibitorios de la lipasa pancreática (IC50: 556.58 µg/mL para EBF y 532.68 µg/mL para FFA), potencial antioxidante, ausencia de toxicidad preliminar y presencia de ácidos gálico y elágico en FFA. Los resultados relevantes en la inhibición de la α-glucosidasa y la lipasa pancreática motivan nuevos estudios para el desarrollo de medicamentos a base de hierbas que ayudan en el tratamiento de pacientes diabéticos.

Optimisation of Bjerkandera adusta culture conditions for the production of α-α-trehalose.

Several factors affect the vegetative growth of fungi, such as temperature, pH, and culture medium. In addition to mycelial growth, these factors affect metabolite production. There are limited studies that have identified the metabolites produced by the fungus Bjerkandera adusta, which have potential biotechnological applications. Here, we evaluated the effects of temperature, culture medium, and incubation time on the production of mycelial mass and metabolites of B. adusta isolated from Pinus taeda. The highest mycelial mass was obtained at 24 °C, in the potato dextrose and malt extract media, upon incubation for 28 and 35 days. The disaccharide α-α-trehalose was for the first time isolated and identified by X-ray diffraction in this fungal genus.

Myrcia hatschbachii: antifungal activity and structural elucidation of ellagic and 3-O-methyl ellagic acids.

Natural products, especially plants, have been investigated as sources of new substances with antimicrobial properties. In this context, the Myrcia genus is extensively researched for presenting such activities. This work aims to evaluate the antifungal, antibacterial, and antioxidant properties of extracts and fractions of stems of Myrcia hatschbachii, also to characterize two phenolic compounds. The antibacterial and antifungal activities were assessed by using the broth microdilution method. The ethyl acetate fraction (FGA) inhibited the growth of Candida albicans at a Minimum Inhibitory Concentration (MIC) of 15.6 µg/mL, presented 40% of phenolic compounds in its composition, obtained the most significant results in antioxidant methods (DPPH, FRAP, ABTS), besides the identification of ellagic and 3-O-methyl ellagic acids by NMR. Considering the relevant antifungal activity revealed by the fraction, new studies can be carried out to encourage the continuous search for antifungal alternatives.

Phytochemical and morpho-anatomical study of the vegetative organs of Psychotria fractistipula L. B.Sm., R.M. Klein & Delprete (Rubiaceae)

Psychotria fractistipula L.B.Sm, R.M. Klein & Delprete (Rubiaceae) is found in the existing Atlantic Forest in the South of Brazil, in the Paraná and Santa Catarina States. The members of Rubiaceae are characterized chemically by the presence of alkaloids, some pharmacological properties of which include antifungal, antibacterial, analgesic, antioxidant, antimutagenic, and antiviral activities. In this study, we report the results of anatomical, morphological, and histochemical analyses of the leaves and stems of the Rubiaceae family member, P. fractistipula. The anatomical analysis involved of light microscopy and scanning electron microscopy. Morpho-anatomical and histochemical characterization were made using standard methodology. The isolated compounds were identified by Nuclear Magnetic Resonance spectroscopic analysis. The following structures are highlighted as the distinctive features of the species: presence of petiolate leaves and a petiole base, leaf blade with smooth cuticle on both surfaces, paracytic stomata, and, dorsiventral mesophyll and presence of trichomes on the leaves and stems. Phytosteroids, identified as β-sitosterol and campesterol, were observed in the hexane fraction of the stem. Future studies should focus on the isolation of other fractions of interest and their characterization through specific biological and cytotoxicity assays.

Antagonistic activity of Diplodia pinea against phytopathogenic fungi.

The ability of Diplodia pinea to inhibit Armillaria sp., Bjerkandera adusta, Botrytis cinerea, and Rhizoctonia sp. mycelium growth was analyzed using the double-culture method. Wild-type fungal strains were incubated in a biochemical oxygen demand incubator using potato agar dextrose medium at 24 ± 2 °C for 35 days in darkness. D. pinea significantly inhibited the growth of all fungi species tested (30.75 to 98.37% inhibition) and showed moderate antagonistic activity (antagonistic index, 14.5). Chemical analysis of D. pinea culture broth extracts revealed steroids, triterpenes, and phenolic compounds. Alkaloids were qualitatively detected in the mycelium crude extract. The presence of these compounds may be related to the antagonistic activity observed. The inhibition ability of D. pinea is due to competition with the tested fungi for substrate and space.