Records of Natural Products Articles

Sphaerocoryne affinis is prevalent in numerous forests throughout Vietnam and has traditionally been used in the production of alcoholic beverages, as well as in folk medicines for treating various diseases. This study provided the first comprehensive investigation into the anti-oxidative stress and anti-inflammatory properties of S. affinis leaves. These results revealed that the S. affinis leaf extract and its fractions demonstrated notable antioxidant activity and stress-mitigating effects, as indicated by the prolonged lifespan of Drosophila melanogaster subjected to paraquat (PQ)-induced oxidative stress. Furthermore, the anti-inflammatory potential of S. affinis leaf extract and its ethyl acetate and hexane fractions was validated through their ability to inhibit NO secretion in LPS-stimulated RAW264.7 macrophage cells. Besides, 12 known bioactive compounds were isolated from the ethyl acetate fraction of S. affinis leaf extract, among which 8 compounds were identified for the first time in the genus Sphaerocoryne. These newly discovered compounds included allantoin, apigenin, rutin, isatin, 3-hydroxy-3-(2-oxopropyl)indolin-2-one, ethylene glycol dibenzoate, nicotiflorin, and 3,3',4,4'-tetrahydroxybiphenyl. These findings emphasized the potential of S. affinis leaves as a valuable source of bioactive compounds, paving the way for the development of innovative healthcare products and natural therapeutic interventions for various diseases.

A previously undescribed lupane-type triterpene (1) and five known compounds (2-6) were isolated from the roots of Ampelopsis grossedentata. The structure of compound 1 was elucidated through comprehensive analysis of spectroscopic data, which included 1D and 2D NMR as well as HRESIMS. The absolute configuration of 1 was resolved by comparing its specific rotation with that of its demethylated derivative 3b-O-trans-p-coumaroylalphitolic acid,and was also supported by comparisons of the experimental and the theoretical ECD spectra. The known compounds were identified as daucosterol (2), ellagic acid (3) and its trimethylated derivative (4), resveratrol (5), and dihydrokaempferol (6) by comparing their NMR data and optical rotations with those in the literature. Compounds 1–6 were tested for their antimicrobial activity against five different bacterial strains. The results indicated that compounds 3, 4, and 6 exhibited weak antibacterial activity, with MIC values ranging from 128 to 256 µg/mL.

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.