Stilbenes, phenanthrenes and antiproliferative activity of .

The phytochemical study of (Orchidaceae) led to the isolation of two new stilbenoids and one new 9,10-dihydrophenanthrene, 4',5-dihydroxy-2',3-dimethoxy-dihydrostilbene (), 3,6'-dihydroxy-4'-methoxy-dihydrostilbene () and 1,2,6-trihydroxy-3,8-dimethoxy-9,10-dihydrophenanthrene (), named cattleymediol, cattleyol and phenanmediol, respectively, in addition to other five known compounds (). The structural elucidations of the isolated compounds were carried out through the analyses of the one-dimensional H,³C and NOE NMR spectra, and the 2D HSQC, HMBC, COSY and NOESY spectra, besides high-resolution mass spectrometry. In addition to this, the crude extract and its main fractions were analysed by ultra-high performance liquid chromatography coupled to high resolution mass spectrometry (UHPLC-QTOF-MS/MS), leading to the putative identification of several other compounds, including flavonoids and organic acids derivatives.

Bioactive natural products from orchids native to the Americas - A review.

The purpose of this review is to provide information on the traditional uses, phytochemical and pharmacological studies performed with species of orchids native to the Americas and the Caribbean Islands. The treatment of inflammation is the most traditional use for plants of this family, specially in Central America, while anti-inflammatory and anticancer assays are oftenly reported in pharmacological investigations. From the chemical point of view, they are sources of phenanthrenoids and stilbenes, rare secondary metabolites not commonly found in other families of plants, as well as cycloartane triterpenes, pyrrolizidine alkaloids and flavonoids.

Chemical profile, antioxidant and anti-inflammatory properties of Miconia albicans (Sw.) Triana (Melastomataceae) fruits extract.

Ethnopharmacological Relevance: Miconia albicans (Sw.) Triana has been widely used in Brazilian popular medicine for the treatment of several diseases. Aerial parts are used as an infusion to treat arthrosis and arthritis, to relieve rheumatic and stomach pains, and intestinal disorders due to its anti-inflammatory, anti-mutagenic anti-nociceptive, digestive and hepatoprotective properties.

Kopsanone and N-oxide isolated from Mart. (Apocynaceae) leaves and their MAO-A inhibitory activity.

Mart., popularly known as 'guatambu' or 'peroba', is found from North American (Mexico) to South American (Argentina) continents and in Brazil. Two indole alkaloids were isolated from leaves of , kopsanone () and unreported (4)-oxide-kopsanone ().

Acyl-Homoserine Lactone from Plant-Associated Pseudomonas sp. Influences Solanum lycopersicum Germination and Root Growth.

It is known that plant and associated bacteria coevolved, but just now the roles of chemical signaling compounds in these intricate relationships have been systematically studied. Many Gram-negative bacteria produce N-acyl-L-homoserine lactones (AHL), chemical signals used in quorum-sensing bacterial communications mechanisms. In recent years, it has been shown that these compounds may also influence the development of plants, acting as allelochemicals, in still not well understood eukaryot-prokaryot interactions.

Cytotoxicity and anti-inflammatory effects of the extract, fractions and alkaloids from (Rubiaceae).

species has been used in folk medicine in the treatment of some diseases including cancer and inflammatory disorders. This work aimed to evaluate the antiproliferative and topical anti-inflammatory activities of the methanolic extract, fractions and two major alkaloids isolated from . Methanolic extract, non-alkaloidal and alkaloidal fractions exhibited strong growth inhibition for ovarian cell lines (OVCAR-3, GI = 3.

Antiproliferative activity and energy calculations of a new triterpene isolated from the palm tree .

Mart () is a palm tree native to South America, widely studied for biodiesel production. The aim of this work was to perform the first phytochemical study of leaves, as well as to do biological assays against human cancer cell lines. A new triterpene of the hopane class named totaiol three known triterpenes , and two phytosteroids were identified.

The ability of farnesol to prevent adhesion and disrupt Fusarium keratoplasticum biofilm.

A biofilm is represented by a community of microorganisms capable of adhering to a surface and producing substances that envelop the cells, forming an extracellular matrix. The extracellular matrix is responsible for protecting microorganisms against environmental stress, hosts the immune system and confers resistance to antimicrobials. Fusarium keratoplasticum is a common species of FSSC (Fusarium solani species complex) associated with human infections, being the most prevalent species related to biofilm formation in hospital water systems and internal pipelines.

Antiproliferative activity and chemical constituents of (Fabaceae).

The aerial parts of were submitted to a phytopharmacological investigation in order to isolate and identify the major secondary metabolites and evaluate its crude extract, fractions and isolated compounds for antiproliferative activity. Seven compounds were isolated and identified as the chalcones 2',4'-dihydroxy-5'-prenylchalcone () and isocordoin (), the flavanone 8-prenylpinocembrin (), the alkaloid 4-hydroxy--methylproline (), the triterpenes lupeol and lupenone. These compounds were identified by nuclear magnetic resonance of H and C data in comparison with literature.

Crispoic acid, a new compound from Laelia marginata (Orchidaceae), and biological evaluations against parasites, human cancer cell lines and Zika virus.

The phytochemical study of Laelia marginata (Lindl.) L. O.

Anti-inflammatory and antiproliferative activities of Ixora brevifolia Benth. (Rubiaceae).

The crude extract and fractions from the branches of Ixora brevifolia, a tree found in the Brazilian Cerrado, were tested for anti-inflammatory and in vitro antiproliferative effects. The crude extract and n-hexane fraction exhibited significant inhibition of ear oedema in mice, while n-hexane-precipitated and chloroform fractions strongly inhibited the myeloperoxidase activity in ear tissue. The n-hexane and n-hexane-precipitated fractions showed strong growth inhibition for glioma cell line and the hydromethanolic fraction inhibited the growth of leukaemia cell line.

Phenolic compounds and anticancer activity of commercial sugarcane cultivated in Brazil.

The cultivation of sugarcane hybrids (X Saccharum officinarum L.) is an important revenue source for the Brazilian economy. Herein it is reported the evaluation of the cytotoxic activity of mid-polarity sugarcane extracts against human cancer cell lines, as well as the isolation of steroids sitosterol, stigmasterol and campesterol, phenolic acids p-hydroxybenzoic, p-hydroxycinnamic, vanillic and ferulic acid, terpenoids α-tocopherol and β-carotene and a novel substance in sugarcane, the flavonoid aglycone tricin (5,7,4-trihydroxy-3,5-dimethoxyflavone).

Acyl-homoserine Lactone from Saccharum × officinarum with Stereochemistry-Dependent Growth Regulatory Activity.

Acyl-homoserine lactones (AHLs) are a class of compounds produced by Gram-negative bacteria that are used in a process of chemical communication called quorum sensing. Much is known about how bacteria use these chemical compounds to control the expression of important factors; however, there have been few reports about the presence and effects of AHLs in plants. In this study, the phytochemical study of leaves and culms of sugar cane (Saccharum × officinarum) led to the identification of N-(3-oxo-octanoyl)homoserine lactone.

Acute toxicity, antiedematogenic activity, and chemical constituents of Palicourea rigida Kunth.

The phytochemical study of the leaves, roots, and flowers of Palicourea rigida led to the isolation of the triterpenes betulinic acid (1) and lupeol (2), the diterpene phytol (3), and the iridoid glycosides sweroside (4) and secoxyloganin (5). These compounds were identified using NMR 1H and 13C and comparing the spectra with published data. We studied the antiedematogenic activity of crude extracts from the organs, and of different fractions, in mice and found that the n-hexane fraction of the leaf extract significantly inhibited the ear edema resulting from croton oil administration.

Bioguided identification of antifungal and antiproliferative compounds from the Brazilian orchid Miltonia flavescens Lindl.

The Orchidaceae family is appreciated worldwide for the beauty of its flowers, and hundreds of species of this family occur in Brazil. Yet little is known about the potential of orchids for therapeutic application. We have investigated bioactive compounds produced by the South Brazilian orchid Miltonia flavescens Lindl.

Methylobacterium-plant interaction genes regulated by plant exudate and quorum sensing molecules.

Bacteria from the genus Methylobacterium interact symbiotically (endophytically and epiphytically) with different plant species. These interactions can promote plant growth or induce systemic resistance, increasing plant fitness. The plant colonization is guided by molecular communication between bacteria-bacteria and bacteria-plants, where the bacteria recognize specific exuded compounds by other bacteria (e.

Chemical constituents of Machaerium hirtum Vell. (Fabaceae) leaves and branches and its anti-inflammatory activity evaluation.

Leaves and branches of Machaerium hirtum Vell. (Fabaceae), native to South America, were subjected to phytopharmacological investigation in order to identify its major chemical constituents and evaluate its extracts, fractions and isolated compounds in assays for anti-inflammatory activities. These were performed using mouse ear edema model, pleurisy and myeloperoxidase activity assays.

Long-chain acyl-homoserine lactones from Methylobacterium mesophilicum: synthesis and absolute configuration.

The acyl-homoserine lactones (acyl-HSLs) produced by Methylobacterium mesophilicum isolated from orange trees infected with the citrus variegated chlorosis (CVC) disease have been studied, revealing the occurrence of six long-chain acyl-HSLs, i.e., the saturated homologues (S)-N-dodecanoyl (1) and (S)-N-tetradecanoyl-HSL (5), the uncommon odd-chain N-tridecanoyl-HSL (3), the new natural product (S)-N-(2E)-dodecenoyl-HSL (2), and the rare unsaturated homologues (S)-N-(7Z)-tetradecenoyl (4) and (S)-N-(2E,7Z)-tetradecadienyl-HSL (6).

Absolute configuration and antimicrobial activity of acylhomoserine lactones.

(S)-N-Heptanoylhomoserine lactone is an uncommon acyl odd-chain natural product employed by many Gram-negative bacteria as a signaling substance in chemical communication mechanisms known as quorum sensing. The absolute configuration determination of the metabolite produced by the phytopathogen Pantoea ananatis Serrano is reported herein. As with all other substances of this class, the lactone moiety possesses S configuration, corroborating the hypothesis that it shares the same biosynthetic pathway as the (S)-N-hexanoylhomoserine lactone and also that some LuxI homologues can accept both hexanoyl- and heptanoyl-ACP as precursors.

Acyl-homoserine lactones produced by Pantoea sp. isolated from the "maize white spot" foliar disease.

The "maize white spot" foliar disease is a problem of increasing importance to Brazilian maize crops. A bacterium isolated from water-soaked lesions from infected maize leaves was pathogenic in biological assays in vivo. It was identified as a Gram-negative, nonsporulating, facultative anaerobic bacterium, belonging to the genus Pantoea.

Structural elucidation and biological activity of acyl-homoserine lactones from the phytopathogen Pantoea ananatis Serrano 1928.

In Gram-negative bacteria, the acyl-homoserine lactones (acyl-HSLs) are the main signaling substances employed in cell-to-cell communication systems. This paper describes the chemical characterization of acyl-HSLs produced by the worldwide-spread phytopathogen Pantoea ananatis (Serrano 1928) by using gas chromatography-electron impact mass spectrometry. The absolute configuration of the major identified substance, (S)-(--)-N-hexanoyl-HSL, was determined with gas chromatography-flame ionization detection with a chiral capillary column.

A new method for asperphenamate synthesis and its antimicrobial activity evaluation.

Asperphenamate is a natural phenylalanine derivative. This compound was produced through a new, two-step synthetic route. It was also evaluated by the antimicrobial activity of the pure substance against Escherichia coli, Staphylococcus aureus and Cladosporium herbarum.

Chemical defense in harvestmen (arachnida, opiliones): do benzoquinone secretions deter invertebrate and vertebrate predators?

Two alkylated 1,4-benzoquinones were identified from the defensive secretion produced by the neotropical harvestman Goniosoma longipes (Gonyleptidae). They were characterized as 2,3-dimethyl-1,4-benzoquinone and 2-ethyl-3-methyl-1,4-benzoquinone. We tested the effectiveness of these benzoquinone secretions against several predator types, including invertebrates and vertebrates.

Acyl-homoserine lactones from Erwinia psidii R. IBSBF 435T, a guava phytopathogen (Psidium guajava L.).

The phytopathogen Erwinia psidii R. IBSBF 435T causes rot in branches, flowers, and fruits of guava (Psidium guajava L.), being responsible for crop losses, and has no effective control.