Improved production of palitantin by design of experiments and semi-synthesis of palitantin derivatives for bioactivity assessment.

A new method for the production and isolation of (+)-palitantin (1) is herein reported, from cultures of the fungal strain Penicillium sp. AMF1a. (+)-Palitantin was isolated in 160 mg/L yield, as an alternative procedure to obtain 1 at a larger scale.

Induction of metabolic variability of the endophytic fungus Xylaria sp. by OSMAC approach and experimental design.

This work has as the main focus, to analyze the behavior of physic-chemical variations from the fungus Xylaria sp., through the OSMAC (One Strain, Many Compounds) approach as an efficient way of obtaining new compounds. To perform such inductions and to explore the variability of the metabolic network of this microorganism, a factorial design was designed to induce variability (or enhancement) of metabolites.

Antiproliferative Flavanoid Dimers Isolated from Brazilian Red Propolis.

Herein reported are results of the chemical and biological investigation of red propolis collected at the Brazilian Northeast coastline. New propolones A-D (-), with a 3-{3-[(2-phenylbenzofuran-3-yl)methyl]phenyl}chromane skeleton; propolonones A-C (-), with a 3-[3-(3-benzylbenzofuran-2-yl)phenyl]chromane skeleton; and propolol A (), with a 6-(3-benzylbenzofuran-2-yl)-3-phenylchromane skeleton, were isolated as constituents of Brazilian red propolis by cytotoxicity-guided assays and structurally identified by analysis of their spectroscopic data. Propolone B () and propolonone A () display significant cytotoxic activities against an ovarian cancer cell line expressing a multiple drug resistance phenotype when compared with doxorubicin.

Approaches for the isolation and identification of hydrophilic, light-sensitive, volatile and minor natural products.

Covering: up to 2019The discovery of new bioactive natural products gained momentum during the last few decades, resulting from instrumentation advances, from the expansion of genome mining and regulation, as well as by exploration of untapped biological sources. However, water-soluble, volatile, minor and photosensitive natural products are yet poorly known. This review discusses the literature reporting the isolation strategies for some of these metabolites.

Secondary Metabolites of Endophytic Actinomycetes: Isolation, Synthesis, Biosynthesis, and Biological Activities.

Endophytic Actinobacteria are a microbial group that is still poorly investigated. Their association with plants constitutes a unique trait conferring specific biological and chemical features to endophytic Actinobacteria. This contribution discusses aspects of endophytic actinobacterial biology and chemistry comprehensively, including the biosynthesis and total synthesis of secondary metabolites produced in culture.

Oxidative functionalization of a halimane diterpenoid achieved by fungal transformation.

Regio and stereoselective activation of sp CH bonds remain one of the major advantages of biocatalysis over traditional chemocatalytic methods. Herein, we describe the oxy-functionalization of halimane diterpenoid 1 by whole cells of three filamentous fungi, aiming to obtain derivatives with desirable biological properties. After incubating 1 with Fusarium oxysporum, Myrothecium verrucaria, and Rhinocladiella similis at different concentrations and incubation times, four known (3, 5, 6, and 7) and three new (2, 4, and 8) halimane derivatives were obtained and characterized.

Biotransformation of labdane and halimane diterpenoids by two filamentous fungi strains.

Biotransformation of natural products by filamentous fungi is a powerful and effective approach to achieve derivatives with valuable new chemical and biological properties. Although diterpenoid substrates usually exhibit good susceptibility towards fungi enzymes, there have been no studies concerning the microbiological transformation of halimane-type diterpenoids up to now. In this work, we investigated the capability of (a fungus isolated from the rhizosphere of ) and (an endophyte) to transform halimane () and labdane () acids isolated from (Fabaceae).

Structure and Absolute Configuration of Diterpenoids from Hymenaea stigonocarpa.

Chemical investigations of the ethanolic extracts from the flowers and leaves of Hymenaea stigonocarpa Mart. ex Hayne afforded one new ent-halimane diterpenoid, 18-hydroxy-ent-halima-1(10),13-(E)-dien-15-oic acid (1), together with five known compounds (2-6). The structural elucidation was performed by means of NMR (COSY, HSQC, HMBC, and NOESY) and MS analyses.