Records of Natural Products Articles

In this study, phytochemical investigation of ethanolic (EtOH 60%, Water 40%) extract from Potentilla kleiniana by reflux extraction was carried out for the isolation and characterization of their chemical structures of seventeen known secondary metabolites. Structure determination of the isolated compounds was carried out using 1D NMR data and mass spectrometry techniques. Compounds 3, 8, 12 and 13 were isolated from P. kleiniana for the first time in this study and were recorded as a new report for the species. Compounds  (2, 6-7, 9, 11 and 14-15)  represent previously unreported constituents within the genus Potentilla. As a result of the α-glucosidase inhibitory activity determination studies performed separately on the isolated compounds, it was determined that compounds 10, 14 and 15 exhibited better inhibition-inhibition percentages of 87.14%, 49.07%, and 86.79%, respectively compared to the positive control acarbose (37.26%). Moreover, compounds 3, 10, 14 and 15 were determined to be secondary metabolites with significant nitric oxide (NO). SAR analyses were performed to understand the relationship between α-glucosidase inhibitory activities and the structures of the molecules, and according to the results of these analyses, it was observed that flavonoid derivatives carrying hydroxyl groups at C-3 and C-7 positions showed higher hypoglycemic activity than their counterparts carrying rhamnose groups at these positions.

One new diterpene with a fused 6-5-6-6 ring system, trichodermanin I (1), along with three known ones, wickerols A and B and trichodermanin F (2-4), were acquired from the extract of Trichoderma atroviride YD-13 isolated from soil. Their chemical structures were determined by interpretation of 1D/2D nuclear magnetic resonance (NMR) and high-resolution electrospray ionization mass spectrometry (HRESIMS) data. Compound 1 was evaluated for inhibiting the growth of four human pathogenic bacteria (Clostridium botulinum, Escherichia coli, Salmonella, and Staphylococcus aureus) and exhibited potential antibacterial activity against C. botulinum, E. coli, and S. aureus with MIC values of 8.0 μg/mL, 32 μg/mL, and 16 μg/mL, respectively.

The consumption of raspberry (Rubus idaeus L.) leaves has a long tradition, especially as a "general pregnancy tea", although the scientific data are insufficient and contradictory. Phytochemical comparation of extracts from cultivated and wild raspberry leaves, in silico prediction of their biological activities and acute toxicity followed by in vitro antiradical activity and effects on the viability/proliferation of HeLa cells and isolated rat uterus were performed. Leaves from cultured (v. Polka) and wild individuals were extracted with distilled water, 70% v/v ethanol or 70% v/v methanol. All samples exhibited high polyphenol content and antiradical activity, with the 70% v/v ethanol extract of wild R. idaeus showing the strongest free radical scavenging ability. In silico analyzes predicted that a large number of raspberry leaves possess anti-inflammatory, apoptosis-agonistic, antinociceptive and NO signaling-related activities. Potentially toxic levels of the tested compounds could not be achieved with regular tea drinking. The tested extracts have no noticeable effects on the viability/proliferation of HeLa cells. The effects on spontaneous contraction of the isolated rat uterus were modest. Although safety is not a concern, further studies are needed to justify or deny the efficacy of raspberry leaf tea in folk medicine for healthy pregnancy and easy delivery.