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Bacteria can synthesize a broad spectrum of multifunctional polysaccharides including extracellular polysaccharides (EPS). Bacterial EPS can be utilized in the food, pharmaceutical, and biomedical areas owing to their physical and rheological properties in addition to generally presenting low toxicity. From an ecological viewpoint, EPS are biodegradable and environment compatible, offering several advantages over synthetic compounds. This study investigated the EPS produced by Klebsiella oxytoca (KO-EPS) by chemically characterizing and evaluating its properties. The monosaccharide components of the KO-EPS were determined by HPLC coupled with a refractive index detector and GC-MS. The KO-EPS was then analyzed by methylation analysis, FT-IR and NMR spectroscopy to give a potential primary structure. KO-EPS demonstrated the ability to stabilize hydrophilic emulsions with various hydrophobic compounds, including hydrocarbons and vegetable and mineral oils. In terms of iron chelation capacity, the KO-EPS could sequester 41.9 % and 34.1 % of the most common iron states, Fe2+ and Fe3+, respectively. Moreover, KO-EPS exhibited an improvement in the viscosity of aqueous dispersion, being proportional to the increase in its concentration and presenting a non-Newtonian pseudoplastic flow behavior. KO-EPS also did not present a cytotoxic effect indicating that the KO-EPS could have potential applications as a natural thickener, bioemulsifier, and bioremediation agent.

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The saprophytic basidiomycete Lentinus crinitus (L.) Fr is a Brazilian native fungus with pantropical occurrence. L. crinitus produces edible fruiting bodies with medicinal, nutritional, and biotechnological applications. The compounds from fungal fruiting bodies can be applied to the preparation of products in the food, cosmetic, biomedical, and pharmaceutical industries. Our aim was to review the literature on L. crinitus concerning its botanical description, geographical distribution, phytochemistry, pharmacological properties, nutritional value, and biotechnology potential (in vitro cultivation and enzyme production). Scientific search engines, including ScienceDirect, CAPES Journals Portal, Google Scholar, PubMed, SciELO, MEDLINE, LILACS, and SciFinder, were consulted to gather data on L. crinitus. The present review is an up-to-date and comprehensive analysis of the phytochemical compounds, phytopharmacological activities, and biotechnological value of L. crinitus. Extracts from L. crinitus have been reported to exhibit numerous in vitro pharmacological activities such as antioxidant, antifungal, antibacterial, antiviral, and anticancer. The substances in these extracts belong to different classes of chemical compounds such as polysaccharides, fatty acids, terpenes, phenolic acids, and flavonoids. Reviews on Brazilian native fungi are of great importance for scientific knowledge, with great applicability as a mirror for species of the same family. The ethnobotanical, phytochemical, pharmacological, ethnomedicinal, and biotechnological properties of L. crinitus highlighted in this review provide information for future studies and commercial exploitation, and reveal that this fungus has enormous potential for pharmaceutical, nutraceutical, biotechnological, and ecological applications.

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Inulin is a polymer of d-fructose, characterized by the presence of a terminal glucose, and are a major component of Stevia rebaudiana roots. This type of polymer has nutritional properties and technological applications, such as fat substitutes in low-calorie foods and as the coating of pharmaceuticals. The aim of this study was to evaluate an alternative method for inulin extraction, in terms of extraction time and yield, since the traditional method of extraction under reflux is both time and energy consuming. Using the response surface methodology (RSM) with Box-Behnken design it was observed that the alternative extraction method using autoclave presented similar yields to the reflux-based method, but with a shorter extraction time, 121 °C by 17.41 min 1H Nuclear Magnetic Resonance and Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-ToF-MS) analysis showed that inulin crude extract from S. rebaudiana roots obtained by autoclave extraction had a higher degree of polymerization when compared to those obtained by the traditional method. Thus, it is concluded that the proposed method using an autoclave is a faster alternative for the extraction of inulin.

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Campomanesia xanthocarpa leaves are a byproduct of fruit production without studies on antioxidant activity. Thus, this study aimed to identify the antioxidant compounds of C. xanthocarpaleaves by ultra-high performance liquid chromatography coupled with electrospray ionization-quadrupole-time of flight-mass spectrometry (UHPLC-ESI/qTOF) and by different in vitro antioxidant methods. The crude extract of C. xanthocarpa leaves had a yield of 15.2% and only five out of 37 fractions of the crude extract had antioxidant activity. The crude extract presented greater antioxidant activity than the isolated fractions. The identified antioxidant compounds were phenolic acids (gallic acid and chlorogenic acid), flavonoids (quercetin and naringenin 7,4'-dimethoxy) and an organic acid (quinic acid). Leaves of C. xanthocarpa have high concentration of antioxidant compounds and it is a promising plant for the development of applications in the food, cosmetic, and pharmaceutical fields. The extraction of antioxidant compounds can add value to the productive chain of this plant.

Las hojas de Campomanesia xanthocarpa son un subproducto de la producción de frutos sin estudios sobre la actividad antioxidante. Así, este estudio tuvo como objetivo identificar los compuestos antioxidantes de las hojas de C. xanthocarpa mediante cromatografía líquida de ultra alta resolución acoplada con espectrometría de ionización-cuadrupolo-tiempo de vuelo-masa por electropulverización (UHPLC-ESI / qTOF) y mediante diferentes métodos antioxidantes in vitro. El extracto crudo de hojas de C. xanthocarpa tuvo un rendimiento del 15,2% y solo cinco de las 37 fracciones del extracto crudo tuvieron actividad antioxidante. El extracto crudo presentó mayor actividad antioxidante que las fracciones aisladas. Los compuestos antioxidantes identificados fueron ácidos fenólicos (ácido gálico y ácido clorogénico), flavonoides (quercetina y naringenina 7,4'-dimetoxi) y un ácido orgánico (ácido quínico). Las hojas de C. xanthocarpa tienen una alta concentración de compuestos antioxidantes y es una planta prometedora para el desarrollo de aplicaciones en los campos alimentario, cosmético y farmacéutico. La extracción de compuestos antioxidantes puede agregar valor a la cadena productiva de esta planta.

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The aim of this study was to establish a sustainable alternative callus culture of Cereus hildmannianus for the production and bioactive determination of phenolic compounds from this species. The conventional callus was cultivated using agar and Murashige and Skoog (MS) medium, while for the alternative culture the agar was replaced with a cotton support covered with filter paper and MS medium (incubated at 32 °C with photoperiod of 16 h), and the morphological characteristics and growth index were assessed (8 weeks). Extracts were obtained by maceration followed by partition, characterized by nuclear magnetic resonance - NMR and ultra-high performance liquid chromatography - UHPLC, quantified (phenolic compounds) by UV-Vis methods, and their antioxidant, antitumor activities, as well as cytotoxicity, were evaluated. The establishment of an alternative callus culture was carried out successfully. Characteristic signals of phenolic compounds were determined by NMR, and 46 compounds with fragment ions were identified using UHPLC analysis. The highest concentrations of phenolic compounds, and greatest antioxidant and antitumor activities, were obtained with the dichloromethane fractions of both callus tissue cultures, which were not cytotoxic. The callus culture from C. hildmannianus has shown promise as a source for the sustainable production of phenolic compounds with antioxidant and antiproliferative activities and thus, has potential use as a natural antitumor product.

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Iron is a fundamental microelement for human life; however, deficiencies or excesses of these metal ions can cause severe complications and mortality. Chelators are compounds that bind and inhibit iron. Ultraviolet-visible (UV-vis) spectrophotometric methods are key analytical tools in the identification of chemical entities, with the benefits of having good precision and accuracy, and the equipment being easily available as well as quick and simple to implement. In this study, we aimed to provide an alternative, cheaper method for the quantification of iron ion chelation by substituting ferrozine for gallic acid and validating its use with UV-vis according to official ANVISA and ICH guidelines. The parameters assessed were specificity, linearity, precision, accuracy, robustness, and finally, the percentage of iron ions chelating was calculated. The results demonstrated that this method was accurate, simple, specific, selective, precise, and reproducible, and was successfully validated for the determination of iron ions chelating. The percentage of iron ions chelating, promoted by the standard chelator EDTA, was 45% and 47% for Fe2+ and Fe3+, respectively. It is concluded that this new method is beneficial in terms of its simplicity, rapidness, low cost, and the fact that it produces very low levels of dangerous residues.(AU)

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This study was to evaluate the biological activity of the extract of Botryosphaeria fabicerciana isolated from leaves of Morus nigra. The volatile compounds from the crude extract were analysed by GC-MS which demonstrate that mellein and ß-orcinaldehyde were are the major compounds. The best minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extract was observed against Gram-positive bacteria, with a MIC of 15.6 µg/mL towards B. cereus and MIC of 62.5 µg/mL towards S. aureus and B. subtilis. MBC values of 31.25 µg/mL, 62.5 µg/mL, and 250 µg/mL were observed towards B. cereus, B. subtilis, and S. aureus, respectively. The cytotoxicity analyses showed CC50 of 115 µg/mL. The crude extract showed antioxidant activity by the DPPH, ABTS, and FRAP assays. Therefore, the extract of the endophytic fungus presented biotechnological potential as an antibacterial and antioxidant agent.

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Abstract Exopolysaccharides (EPS) produced by Klebsiella oxytoca are of environmental, pharmaceutical, and medicinal interest. However, studies about the anti-inflammatory activity of EPS produced by this microorganism still remain limited. The aim of this study was to produce, characterize, and evaluate the anti-inflammatory activity of EPS from K. oxytoca in a pleurisy model. Colorimetric analysis revealed that precipitated crude exopolysaccharides (KEPSC) and deproteinated exopolysaccharides (KEPS) present high levels of total carbohydrates (65.57% and 62.82%, respectively). Analyses of uronic acid (7.90% in KEPSC and 6.21% in KEPS) and pyruvic acid (3.01% in KEPSC and 1.68% in KEPS) confirm that the EPS are acidic. Gas chromatography-mass spectrometry analyses demonstrated that the EPS consisted of rhamnose (29.83%), glucose (11.21%), galactose (52.45%), and mannose (6.50%). The treatment of an experimental pleurisy model in rats through subcutaneous administration of 50, 100, 200, and 400 mg/kg of KEPS decreased both the volume of inflammatory exudate and the number of leukocytes recruited to the pleural cavity. The present data showed that EPS production by K. oxytoca using the method described is easy to perform and results in a good yield. In addition, we show that KEPS exhibit anti-inflammatory activity when administered subcutaneously in rats.

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In this work, the antibacterial activity of a crude extract of the endophytic fungus Flavodon flavus (JB257), isolated from leaves of Justicia brandegeana, was evaluated against both the vegetative and sporulated forms of Alicyclobacillus acidoterrestris. The microdilution technique was performed in order to determine the antibacterial activity of the crude extract alone as well as in combination with the bacteriocin, nisin. The minimum inhibitory concentration (MIC) of the crude extract and nisin alone against A. acidoterrestris vegetative forms were 250 µg/mL and 31.5 µg/mL, respectively, while the minimum bactericidal concentrations (MBC) were 1000 µg/mL and 62.5 µg/mL,respectively. For A. acidoterrestris spores, treatment with the crude extract at a concentration of 500 µg/mL caused a 47% reduction in growth, while nisin at 62.5 µg/mL could reduce 100% of the growth. The in vitro evaluation of the crude extract combined with nisin against A. acidoterrestris by the Checkerboard method showed a synergistic interaction between the two compounds. In addition, greater selectivity towards bacterial cells over host cells, a human hepatocyte cell line, was achieved when the crude extract was combined with nisin, Using scanning electron microscopy, interferences in the cell membrane of A. acidoterrestris could be observed after treatment with the crude extract. The results presented in this study indicate that the crude extract of the endophyte F. flavus has biotechnological potential in the food industry, especially for the treatment of orange juices through the control of A. acidoterrestris.

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