Chemical studies of a Bacillus endophyticus isolated from a Bahamian hypersaline microbial mat led to the isolation of bacillamides B and C, new tryptamide thiazole metabolites. Bioassay-guided fractionation using a HPLC-UV-MS bioassay technique enabled the detection of these trace fermentation products, and their total structures were elucidated by combined spectroscopic techniques.

Introduction: Chemical diffusion of cations and atoms in silicates and metals can promote large isotopic fractionation [1]. An empirical formula relates the diffusion coefficients of two isotopes of an element to their mass ratios through D 1 /D 2 =(m 2 /m 1)

This review provides an overview of two complementary approaches to identify biologically active compounds for studies in chemical ecology. The first is activity-guided fractionation and the second is metabolomics, particularly focusing on a new liquid chromatography-mass spectrometry-based method called isotopic ratio outlier analysis. To illustrate examples using these approaches, we review r...

Bioassay-guided fractionation of an EtOAc/MeOH extract of Adenaria floribunda young leaves using MCF-7, H-460, and SF-268 cancer cell lines yielded four new active compounds named adenaflorins A-D (1-4). Their chemical structures were determined by spectroscopic means. Adenaflorin A (1) was the most cytotoxic.

Many species belonging to the Scrophularia genus have been used since ancient times as folk remedies for many medical conditions such as scrofulas, scabies, tumors, eczema, psoriasis, inflammations. The aim of this study was to characterize the matrix metalloproteinases (MMPs) inhibitor compounds of the Scrophularia striata extract by bio-guide fractionation. The aerial parts of S. striata were...

Many species belonging to the Scrophularia genus have been used since ancient times as folk remedies for many medical conditions such as scrofulas, scabies, tumors, eczema, psoriasis, inflammations. The aim of this study was to characterize the matrix metalloproteinases (MMPs) inhibitor compounds of the Scrophularia striata extract by bio-guide fractionation. The aerial parts of S. striata were...

many species belonging to the scrophularia genus have been used since ancient times as folk remedies for many medical conditions such as scrofulas, scabies, tumors, eczema, psoriasis, inflammations. the aim of this study was to characterize the matrix metalloproteinases (mmps) inhibitor compounds of the scrophularia striata extract by bio-guide fractionation. the aerial parts of s. striata were...

Even though hulless barley is widely known due to its nutritional potential, in Brazil it is only grown at a few agricultural experimental stations. There is no published data about the chemical composition of Brazilian hulless barley varieties; however, research laboratories have studied their agronomical characteristics. The objectives of this study were to present the chemical characterizati...

Nearly all chemical processes fractionate 17O and 18O in a mass-dependent way relative to 16O, a major exception being the formation of ozone from diatomic oxygen in the presence of UV radiation or electrical discharge. Investigation of oxygen three-isotope behavior during thermal decomposition of naturally occurring carbonates of calcium and magnesium in vacuo has revealed that, surprisingly, ...

This study shows that the androgen receptor agonistic potency is clearly concealed by the effects of androgen receptor antagonists in a total sediment extract, demonstrating that toxicity screening of total extracts is not enough to evaluate the full in vitro endocrine disrupting potential of a complex chemical mixture, as encountered in the environment. The anti-androgenic compounds were maski...